First time reporting problems, sorry if this is a bit unprofessional. I got this Fifine Amplitank SC1 audio interface used. Pretty sure these issues aren't electrical given it works on Windows 10 & Linux. On OpenBSD 7.8 and -current: With most usb ports, after seconds-to-minutes of playback I get repeatable buzzing, popping, interfering noise. Playback tested with aucat -i, mpv, vlc, qutebrowser, ungoogled chromium. Recording tested with aucat -o, works as expected.
I used usbdevs to figure out what usb ports correspond to what controller. xhci-based ports on my laptops let me playback my audio with no issues. All ehci ports everywhere are noisy no matter what. And most importantly my PC xhci hub is noisy. It has USB-A and USB-C. When using USB-C, the port is disabled: uhub0: port 2, set config 0 at addr 2 failed uhub0: device problem, disabling port 2 If I use USB-A as is, the noise is there. If I use an additional USB-A hub adapter, it works as expected. This message leads me to my current hypothesis: https://marc.info/?l=openbsd-bugs&m=159680326419525&w=2 The fact that a usb hub helps with xhci on my desktop, possibly means that it uses usb 1.1? If I'm interpreting the outputs correctly, this is the case: dmesg: uaudio0 at uhub3 port 3 configuration 1 interface 1 "fifine Microphones fifine Ampli1" rev 1.10/1.00 addr 8 uaudio0: class v1, full-speed, sync, channels: 2 play, 2 rec, 6 ctls audio1 at uaudio0 uhidev0 at uhub3 port 3 configuration 1 interface 3 "fifine Microphones fifine Ampli1" rev 1.10/1.00 addr 8 uhidev0: iclass 3/0, 2 report ids ucc0 at uhidev0 reportid 1: 17 usages, 7 keys, enum wskbd1 at ucc0 mux 1 wskbd1: connecting to wsdisplay0 uhid5 at uhidev0 reportid 2: input=1, output=0, feature=0 lsusb: Bus 001 Device 007: ID 1a40:0101 Terminus Technology Inc. 4-Port HUB Device Descriptor: bLength 18 bDescriptorType 1 bcdUSB 2.00 bDeviceClass 9 Hub bDeviceSubClass 0 Unused bDeviceProtocol 1 Single TT bMaxPacketSize0 64 idVendor 0x1a40 Terminus Technology Inc. idProduct 0x0101 4-Port HUB bcdDevice 1.11 iManufacturer 0 iProduct 1 USB 2.0 Hub iSerial 0 bNumConfigurations 1 Configuration Descriptor: bLength 9 bDescriptorType 2 wTotalLength 25 bNumInterfaces 1 bConfigurationValue 1 iConfiguration 0 bmAttributes 0xe0 Self Powered Remote Wakeup MaxPower 100mA Interface Descriptor: bLength 9 bDescriptorType 4 bInterfaceNumber 0 bAlternateSetting 0 bNumEndpoints 1 bInterfaceClass 9 Hub bInterfaceSubClass 0 Unused bInterfaceProtocol 0 Full speed (or root) hub iInterface 0 Endpoint Descriptor: bLength 7 bDescriptorType 5 bEndpointAddress 0x81 EP 1 IN bmAttributes 3 Transfer Type Interrupt Synch Type None Usage Type Data wMaxPacketSize 0x0001 1x 1 bytes bInterval 12 Hub Descriptor: bLength 9 bDescriptorType 41 nNbrPorts 4 wHubCharacteristic 0x0000 Ganged power switching Ganged overcurrent protection TT think time 8 FS bits bPwrOn2PwrGood 50 * 2 milli seconds bHubContrCurrent 100 milli Ampere DeviceRemovable 0x00 PortPwrCtrlMask 0xff Hub Port Status: Port 1: 0000.0100 power Port 2: 0000.0100 power Port 3: 0000.0103 power enable connect Port 4: 0000.0100 power Device Qualifier (for other device speed): bLength 10 bDescriptorType 6 bcdUSB 2.00 bDeviceClass 9 Hub bDeviceSubClass 0 Unused bDeviceProtocol 0 Full speed (or root) hub bMaxPacketSize0 64 bNumConfigurations 1 Device Status: 0x0001 Self Powered Bus 001 Device 008: ID 3142:00c1 Device Descriptor: bLength 18 bDescriptorType 1 bcdUSB 1.10 bDeviceClass 0 (Defined at Interface level) bDeviceSubClass 0 bDeviceProtocol 0 bMaxPacketSize0 16 idVendor 0x3142 idProduct 0x00c1 bcdDevice 1.00 iManufacturer 1 fifine Microphones iProduct 2 fifine Ampli1 iSerial 3 REV1.0 bNumConfigurations 1 Configuration Descriptor: bLength 9 bDescriptorType 2 wTotalLength 235 bNumInterfaces 4 bConfigurationValue 1 iConfiguration 0 bmAttributes 0x80 (Bus Powered) MaxPower 100mA Interface Descriptor: bLength 9 bDescriptorType 4 bInterfaceNumber 0 bAlternateSetting 0 bNumEndpoints 0 bInterfaceClass 1 Audio bInterfaceSubClass 1 Control Device bInterfaceProtocol 0 iInterface 0 AudioControl Interface Descriptor: bLength 10 bDescriptorType 36 bDescriptorSubtype 1 (HEADER) bcdADC 1.00 wTotalLength 82 bInCollection 2 baInterfaceNr( 0) 1 baInterfaceNr( 1) 2 AudioControl Interface Descriptor: bLength 12 bDescriptorType 36 bDescriptorSubtype 2 (INPUT_TERMINAL) bTerminalID 1 wTerminalType 0x0101 USB Streaming bAssocTerminal 0 bNrChannels 2 wChannelConfig 0x0003 Left Front (L) Right Front (R) iChannelNames 0 iTerminal 0 AudioControl Interface Descriptor: bLength 12 bDescriptorType 36 bDescriptorSubtype 2 (INPUT_TERMINAL) bTerminalID 2 wTerminalType 0x0201 Microphone bAssocTerminal 0 bNrChannels 2 wChannelConfig 0x0003 Left Front (L) Right Front (R) iChannelNames 0 iTerminal 0 AudioControl Interface Descriptor: bLength 9 bDescriptorType 36 bDescriptorSubtype 3 (OUTPUT_TERMINAL) bTerminalID 6 wTerminalType 0x0301 Speaker bAssocTerminal 0 bSourceID 9 iTerminal 0 AudioControl Interface Descriptor: bLength 9 bDescriptorType 36 bDescriptorSubtype 3 (OUTPUT_TERMINAL) bTerminalID 7 wTerminalType 0x0101 USB Streaming bAssocTerminal 0 bSourceID 8 iTerminal 0 AudioControl Interface Descriptor: bLength 7 bDescriptorType 36 bDescriptorSubtype 5 (SELECTOR_UNIT) bUnitID 8 bNrInPins 1 baSource( 0) 10 iSelector 0 AudioControl Interface Descriptor: bLength 13 bDescriptorType 36 bDescriptorSubtype 6 (FEATURE_UNIT) bUnitID 9 bSourceID 1 bControlSize 2 bmaControls( 0) 0x01 bmaControls( 0) 0x00 Mute Control bmaControls( 1) 0x02 bmaControls( 1) 0x00 Volume Control bmaControls( 2) 0x02 bmaControls( 2) 0x00 Volume Control iFeature 0 AudioControl Interface Descriptor: bLength 10 bDescriptorType 36 bDescriptorSubtype 6 (FEATURE_UNIT) bUnitID 10 bSourceID 2 bControlSize 1 bmaControls( 0) 0x01 Mute Control bmaControls( 1) 0x02 Volume Control bmaControls( 2) 0x02 Volume Control iFeature 0 Interface Descriptor: bLength 9 bDescriptorType 4 bInterfaceNumber 1 bAlternateSetting 0 bNumEndpoints 0 bInterfaceClass 1 Audio bInterfaceSubClass 2 Streaming bInterfaceProtocol 0 iInterface 0 Interface Descriptor: bLength 9 bDescriptorType 4 bInterfaceNumber 1 bAlternateSetting 1 bNumEndpoints 1 bInterfaceClass 1 Audio bInterfaceSubClass 2 Streaming bInterfaceProtocol 0 iInterface 0 AudioStreaming Interface Descriptor: bLength 7 bDescriptorType 36 bDescriptorSubtype 1 (AS_GENERAL) bTerminalLink 1 bDelay 1 frames wFormatTag 1 PCM AudioStreaming Interface Descriptor: bLength 14 bDescriptorType 36 bDescriptorSubtype 2 (FORMAT_TYPE) bFormatType 1 (FORMAT_TYPE_I) bNrChannels 2 bSubframeSize 2 bBitResolution 16 bSamFreqType 2 Discrete tSamFreq[ 0] 44100 tSamFreq[ 1] 48000 Endpoint Descriptor: bLength 9 bDescriptorType 5 bEndpointAddress 0x01 EP 1 OUT bmAttributes 13 Transfer Type Isochronous Synch Type Synchronous Usage Type Data wMaxPacketSize 0x00c8 1x 200 bytes bInterval 1 bRefresh 0 bSynchAddress 0 AudioControl Endpoint Descriptor: bLength 7 bDescriptorType 37 bDescriptorSubtype 1 (EP_GENERAL) bmAttributes 0x01 Sampling Frequency bLockDelayUnits 0 Undefined wLockDelay 0 Undefined Interface Descriptor: bLength 9 bDescriptorType 4 bInterfaceNumber 2 bAlternateSetting 0 bNumEndpoints 0 bInterfaceClass 1 Audio bInterfaceSubClass 2 Streaming bInterfaceProtocol 0 iInterface 0 Interface Descriptor: bLength 9 bDescriptorType 4 bInterfaceNumber 2 bAlternateSetting 1 bNumEndpoints 1 bInterfaceClass 1 Audio bInterfaceSubClass 2 Streaming bInterfaceProtocol 0 iInterface 0 AudioStreaming Interface Descriptor: bLength 7 bDescriptorType 36 bDescriptorSubtype 1 (AS_GENERAL) bTerminalLink 7 bDelay 1 frames wFormatTag 1 PCM AudioStreaming Interface Descriptor: bLength 14 bDescriptorType 36 bDescriptorSubtype 2 (FORMAT_TYPE) bFormatType 1 (FORMAT_TYPE_I) bNrChannels 2 bSubframeSize 2 bBitResolution 16 bSamFreqType 2 Discrete tSamFreq[ 0] 44100 tSamFreq[ 1] 48000 Endpoint Descriptor: bLength 9 bDescriptorType 5 bEndpointAddress 0x82 EP 2 IN bmAttributes 5 Transfer Type Isochronous Synch Type Asynchronous Usage Type Data wMaxPacketSize 0x00c8 1x 200 bytes bInterval 1 bRefresh 0 bSynchAddress 0 AudioControl Endpoint Descriptor: bLength 7 bDescriptorType 37 bDescriptorSubtype 1 (EP_GENERAL) bmAttributes 0x01 Sampling Frequency bLockDelayUnits 0 Undefined wLockDelay 0 Undefined Interface Descriptor: bLength 9 bDescriptorType 4 bInterfaceNumber 3 bAlternateSetting 0 bNumEndpoints 1 bInterfaceClass 3 Human Interface Device bInterfaceSubClass 0 No Subclass bInterfaceProtocol 0 None iInterface 0 HID Device Descriptor: bLength 9 bDescriptorType 33 bcdHID 1.00 bCountryCode 0 Not supported bNumDescriptors 1 bDescriptorType 34 Report wDescriptorLength 104 Report Descriptor: (length is 104) Item(Global): Usage Page, data= [ 0x0c ] 12 Consumer Item(Local ): Usage, data= [ 0x01 ] 1 Consumer Control Item(Main ): Collection, data= [ 0x01 ] 1 Application Item(Global): Report ID, data= [ 0x01 ] 1 Item(Global): Logical Minimum, data= [ 0x00 ] 0 Item(Global): Logical Maximum, data= [ 0x01 ] 1 Item(Local ): Usage, data= [ 0xe9 ] 233 Volume Increment Item(Local ): Usage, data= [ 0xea ] 234 Volume Decrement Item(Global): Report Size, data= [ 0x01 ] 1 Item(Global): Report Count, data= [ 0x02 ] 2 Item(Main ): Input, data= [ 0x42 ] 66 Data Variable Absolute No_Wrap Linear Preferred_State Null_State Non_Volatile Bitfield Item(Local ): Usage, data= [ 0xcd ] 205 Play/Pause Item(Local ): Usage, data= [ 0xb5 ] 181 Scan Next Track Item(Local ): Usage, data= [ 0xb6 ] 182 Scan Previous Track Item(Local ): Usage, data= [ 0xb7 ] 183 Stop Item(Local ): Usage, data= [ 0xe2 ] 226 Mute Item(Global): Report Count, data= [ 0x05 ] 5 Item(Main ): Input, data= [ 0x06 ] 6 Data Variable Relative No_Wrap Linear Preferred_State No_Null_Position Non_Volatile Bitfield Item(Global): Usage Page, data= [ 0xff 0x01 ] 511 (null) Item(Local ): Usage, data= [ 0x01 ] 1 (null) Item(Global): Report Count, data= [ 0x01 ] 1 Item(Main ): Input, data= [ 0x06 ] 6 Data Variable Relative No_Wrap Linear Preferred_State No_Null_Position Non_Volatile Bitfield Item(Global): Usage Page, data= [ 0x0c ] 12 Consumer Item(Local ): Usage, data= [ 0x00 ] 0 Unassigned Item(Global): Report Count, data= [ 0x08 ] 8 Item(Main ): Input, data= [ 0x06 ] 6 Data Variable Relative No_Wrap Linear Preferred_State No_Null_Position Non_Volatile Bitfield Item(Local ): Usage, data= [ 0x00 ] 0 Unassigned Item(Global): Report Size, data= [ 0x08 ] 8 Item(Global): Report Count, data= [ 0x02 ] 2 Item(Main ): Input, data= [ 0x06 ] 6 Data Variable Relative No_Wrap Linear Preferred_State No_Null_Position Non_Volatile Bitfield Item(Global): Usage Page, data= [ 0xff 0x07 ] 2047 (null) Item(Local ): Usage, data= [ 0x01 ] 1 (null) Item(Global): Report Count, data= [ 0x0b ] 11 Item(Main ): Input, data= [ 0x02 ] 2 Data Variable Absolute No_Wrap Linear Preferred_State No_Null_Position Non_Volatile Bitfield Item(Local ): Usage, data= [ 0x00 ] 0 (null) Item(Global): Report Count, data= [ 0x0f ] 15 Item(Main ): Output, data= [ 0x02 ] 2 Data Variable Absolute No_Wrap Linear Preferred_State No_Null_Position Non_Volatile Bitfield Item(Main ): End Collection, data=none Item(Global): Usage Page, data= [ 0x0b ] 11 Telephony Item(Local ): Usage, data= [ 0x05 ] 5 Headset Item(Main ): Collection, data= [ 0x01 ] 1 Application Item(Global): Report ID, data= [ 0x02 ] 2 Item(Local ): Usage, data= [ 0x20 ] 32 Hook Switch Item(Global): Logical Minimum, data= [ 0x00 ] 0 Item(Global): Logical Maximum, data= [ 0x01 ] 1 Item(Global): Report Count, data= [ 0x01 ] 1 Item(Global): Report Size, data= [ 0x01 ] 1 Item(Main ): Input, data= [ 0x23 ] 35 Constant Variable Absolute No_Wrap Linear No_Preferred_State No_Null_Position Non_Volatile Bitfield Item(Global): Report Count, data= [ 0x01 ] 1 Item(Global): Report Size, data= [ 0x07 ] 7 Item(Main ): Input, data= [ 0x07 ] 7 Constant Variable Relative No_Wrap Linear Preferred_State No_Null_Position Non_Volatile Bitfield Item(Main ): End Collection, data=none Endpoint Descriptor: bLength 7 bDescriptorType 5 bEndpointAddress 0x87 EP 7 IN bmAttributes 3 Transfer Type Interrupt Synch Type None Usage Type Data wMaxPacketSize 0x0010 1x 16 bytes bInterval 2 Device Status: 0x0000 (Bus Powered) Is there a way to force it to be USB2? It was advertised as 2.0, and I wasn't even sure if it can do 1.1. Seems like it can, poorly. A different perfectly working uaudio device I have is Kiwi Ears Ardor, and it seems to be 2.0: dmesg: uaudio0 at uhub3 port 3 configuration 1 interface 1 "Generic Kiwi Ears Ardor" rev 2.00/1.00 addr 8 uaudio0: class v1, full-speed, sync, channels: 2 play, 2 rec, 5 ctls audio1 at uaudio0 uhidev0 at uhub3 port 3 configuration 1 interface 3 "Generic Kiwi Ears Ardor" rev 2.00/1.00 addr 8 uhidev0: iclass 3/0, 1 report id ucc0 at uhidev0 reportid 1: 8 usages, 6 keys, enum wskbd1 at ucc0 mux 1 wskbd1: connecting to wsdisplay0 lsusb: Bus 000 Device 002: ID 0225:0d42 Device Descriptor: bLength 18 bDescriptorType 1 bcdUSB 2.00 bDeviceClass 0 (Defined at Interface level) bDeviceSubClass 0 bDeviceProtocol 0 bMaxPacketSize0 64 idVendor 0x0225 idProduct 0x0d42 bcdDevice 1.00 iManufacturer 1 Generic iProduct 2 Kiwi Ears Ardor iSerial 3 20210726905666 bNumConfigurations 1 Configuration Descriptor: bLength 9 bDescriptorType 2 wTotalLength 336 bNumInterfaces 4 bConfigurationValue 1 iConfiguration 0 bmAttributes 0x80 (Bus Powered) MaxPower 100mA Interface Descriptor: bLength 9 bDescriptorType 4 bInterfaceNumber 0 bAlternateSetting 0 bNumEndpoints 0 bInterfaceClass 1 Audio bInterfaceSubClass 1 Control Device bInterfaceProtocol 0 iInterface 0 AudioControl Interface Descriptor: bLength 10 bDescriptorType 36 bDescriptorSubtype 1 (HEADER) bcdADC 1.00 wTotalLength 85 bInCollection 2 baInterfaceNr( 0) 1 baInterfaceNr( 1) 2 AudioControl Interface Descriptor: bLength 12 bDescriptorType 36 bDescriptorSubtype 2 (INPUT_TERMINAL) bTerminalID 1 wTerminalType 0x0101 USB Streaming bAssocTerminal 0 bNrChannels 2 wChannelConfig 0x0003 Left Front (L) Right Front (R) iChannelNames 0 iTerminal 0 AudioControl Interface Descriptor: bLength 13 bDescriptorType 36 bDescriptorSubtype 4 (MIXER_UNIT) bUnitID 6 bNrInPins 2 baSourceID( 0) 5 baSourceID( 1) 5 bNrChannels 2 wChannelConfig 0x0003 Left Front (L) Right Front (R) iChannelNames 0 bmControls 0x00 iMixer 0 AudioControl Interface Descriptor: bLength 10 bDescriptorType 36 bDescriptorSubtype 6 (FEATURE_UNIT) bUnitID 2 bSourceID 1 bControlSize 1 bmaControls( 0) 0x01 Mute Control bmaControls( 1) 0x02 Volume Control bmaControls( 2) 0x02 Volume Control iFeature 0 AudioControl Interface Descriptor: bLength 9 bDescriptorType 36 bDescriptorSubtype 3 (OUTPUT_TERMINAL) bTerminalID 3 wTerminalType 0x0302 Headphones bAssocTerminal 0 bSourceID 2 iTerminal 0 AudioControl Interface Descriptor: bLength 12 bDescriptorType 36 bDescriptorSubtype 2 (INPUT_TERMINAL) bTerminalID 4 wTerminalType 0x0201 Microphone bAssocTerminal 0 bNrChannels 2 wChannelConfig 0x0003 Left Front (L) Right Front (R) iChannelNames 0 iTerminal 0 AudioControl Interface Descriptor: bLength 10 bDescriptorType 36 bDescriptorSubtype 6 (FEATURE_UNIT) bUnitID 5 bSourceID 4 bControlSize 1 bmaControls( 0) 0x03 Mute Control Volume Control bmaControls( 1) 0x00 bmaControls( 2) 0x00 iFeature 0 AudioControl Interface Descriptor: bLength 9 bDescriptorType 36 bDescriptorSubtype 3 (OUTPUT_TERMINAL) bTerminalID 6 wTerminalType 0x0101 USB Streaming bAssocTerminal 0 bSourceID 5 iTerminal 0 Interface Descriptor: bLength 9 bDescriptorType 4 bInterfaceNumber 1 bAlternateSetting 0 bNumEndpoints 0 bInterfaceClass 1 Audio bInterfaceSubClass 2 Streaming bInterfaceProtocol 0 iInterface 0 Interface Descriptor: bLength 9 bDescriptorType 4 bInterfaceNumber 1 bAlternateSetting 1 bNumEndpoints 1 bInterfaceClass 1 Audio bInterfaceSubClass 2 Streaming bInterfaceProtocol 0 iInterface 0 AudioStreaming Interface Descriptor: bLength 7 bDescriptorType 36 bDescriptorSubtype 1 (AS_GENERAL) bTerminalLink 1 bDelay 1 frames wFormatTag 1 PCM AudioStreaming Interface Descriptor: bLength 17 bDescriptorType 36 bDescriptorSubtype 2 (FORMAT_TYPE) bFormatType 1 (FORMAT_TYPE_I) bNrChannels 2 bSubframeSize 2 bBitResolution 16 bSamFreqType 3 Discrete tSamFreq[ 0] 44100 tSamFreq[ 1] 48000 tSamFreq[ 2] 96000 Endpoint Descriptor: bLength 9 bDescriptorType 5 bEndpointAddress 0x03 EP 3 OUT bmAttributes 13 Transfer Type Isochronous Synch Type Synchronous Usage Type Data wMaxPacketSize 0x0240 1x 576 bytes bInterval 1 bRefresh 0 bSynchAddress 0 AudioControl Endpoint Descriptor: bLength 7 bDescriptorType 37 bDescriptorSubtype 1 (EP_GENERAL) bmAttributes 0x01 Sampling Frequency bLockDelayUnits 1 Milliseconds wLockDelay 1 Milliseconds Interface Descriptor: bLength 9 bDescriptorType 4 bInterfaceNumber 1 bAlternateSetting 2 bNumEndpoints 1 bInterfaceClass 1 Audio bInterfaceSubClass 2 Streaming bInterfaceProtocol 0 iInterface 0 AudioStreaming Interface Descriptor: bLength 7 bDescriptorType 36 bDescriptorSubtype 1 (AS_GENERAL) bTerminalLink 1 bDelay 1 frames wFormatTag 1 PCM AudioStreaming Interface Descriptor: bLength 17 bDescriptorType 36 bDescriptorSubtype 2 (FORMAT_TYPE) bFormatType 1 (FORMAT_TYPE_I) bNrChannels 2 bSubframeSize 3 bBitResolution 24 bSamFreqType 3 Discrete tSamFreq[ 0] 44100 tSamFreq[ 1] 48000 tSamFreq[ 2] 96000 Endpoint Descriptor: bLength 9 bDescriptorType 5 bEndpointAddress 0x03 EP 3 OUT bmAttributes 13 Transfer Type Isochronous Synch Type Synchronous Usage Type Data wMaxPacketSize 0x0240 1x 576 bytes bInterval 1 bRefresh 0 bSynchAddress 0 AudioControl Endpoint Descriptor: bLength 7 bDescriptorType 37 bDescriptorSubtype 1 (EP_GENERAL) bmAttributes 0x01 Sampling Frequency bLockDelayUnits 1 Milliseconds wLockDelay 1 Milliseconds Interface Descriptor: bLength 9 bDescriptorType 4 bInterfaceNumber 2 bAlternateSetting 0 bNumEndpoints 0 bInterfaceClass 1 Audio bInterfaceSubClass 2 Streaming bInterfaceProtocol 0 iInterface 0 Interface Descriptor: bLength 9 bDescriptorType 4 bInterfaceNumber 2 bAlternateSetting 1 bNumEndpoints 1 bInterfaceClass 1 Audio bInterfaceSubClass 2 Streaming bInterfaceProtocol 0 iInterface 0 AudioStreaming Interface Descriptor: bLength 7 bDescriptorType 36 bDescriptorSubtype 1 (AS_GENERAL) bTerminalLink 6 bDelay 1 frames wFormatTag 1 PCM AudioStreaming Interface Descriptor: bLength 14 bDescriptorType 36 bDescriptorSubtype 2 (FORMAT_TYPE) bFormatType 1 (FORMAT_TYPE_I) bNrChannels 2 bSubframeSize 2 bBitResolution 16 bSamFreqType 2 Discrete tSamFreq[ 0] 48000 tSamFreq[ 1] 44100 Endpoint Descriptor: bLength 9 bDescriptorType 5 bEndpointAddress 0x83 EP 3 IN bmAttributes 13 Transfer Type Isochronous Synch Type Synchronous Usage Type Data wMaxPacketSize 0x0120 1x 288 bytes bInterval 1 bRefresh 0 bSynchAddress 0 AudioControl Endpoint Descriptor: bLength 7 bDescriptorType 37 bDescriptorSubtype 1 (EP_GENERAL) bmAttributes 0x01 Sampling Frequency bLockDelayUnits 0 Undefined wLockDelay 0 Undefined Interface Descriptor: bLength 9 bDescriptorType 4 bInterfaceNumber 2 bAlternateSetting 2 bNumEndpoints 1 bInterfaceClass 1 Audio bInterfaceSubClass 2 Streaming bInterfaceProtocol 0 iInterface 0 AudioStreaming Interface Descriptor: bLength 7 bDescriptorType 36 bDescriptorSubtype 1 (AS_GENERAL) bTerminalLink 6 bDelay 1 frames wFormatTag 1 PCM AudioStreaming Interface Descriptor: bLength 14 bDescriptorType 36 bDescriptorSubtype 2 (FORMAT_TYPE) bFormatType 1 (FORMAT_TYPE_I) bNrChannels 2 bSubframeSize 3 bBitResolution 24 bSamFreqType 2 Discrete tSamFreq[ 0] 48000 tSamFreq[ 1] 44100 Endpoint Descriptor: bLength 9 bDescriptorType 5 bEndpointAddress 0x83 EP 3 IN bmAttributes 13 Transfer Type Isochronous Synch Type Synchronous Usage Type Data wMaxPacketSize 0x0120 1x 288 bytes bInterval 1 bRefresh 0 bSynchAddress 0 AudioControl Endpoint Descriptor: bLength 7 bDescriptorType 37 bDescriptorSubtype 1 (EP_GENERAL) bmAttributes 0x01 Sampling Frequency bLockDelayUnits 0 Undefined wLockDelay 0 Undefined Interface Descriptor: bLength 9 bDescriptorType 4 bInterfaceNumber 3 bAlternateSetting 0 bNumEndpoints 1 bInterfaceClass 3 Human Interface Device bInterfaceSubClass 0 No Subclass bInterfaceProtocol 0 None iInterface 0 HID Device Descriptor: bLength 9 bDescriptorType 33 bcdHID 2.01 bCountryCode 0 Not supported bNumDescriptors 1 bDescriptorType 34 Report wDescriptorLength 47 Report Descriptor: (length is 47) Item(Global): Usage Page, data= [ 0x0c ] 12 Consumer Item(Local ): Usage, data= [ 0x01 ] 1 Consumer Control Item(Main ): Collection, data= [ 0x01 ] 1 Application Item(Global): Report ID, data= [ 0x01 ] 1 Item(Global): Logical Minimum, data= [ 0x00 ] 0 Item(Global): Logical Maximum, data= [ 0x01 ] 1 Item(Local ): Usage, data= [ 0xcd ] 205 Play/Pause Item(Local ): Usage, data= [ 0xe9 ] 233 Volume Increment Item(Local ): Usage, data= [ 0xea ] 234 Volume Decrement Item(Local ): Usage, data= [ 0xcf ] 207 (null) Item(Local ): Usage, data= [ 0x40 ] 64 Menu Item(Local ): Usage, data= [ 0xb5 ] 181 Scan Next Track Item(Local ): Usage, data= [ 0xb6 ] 182 Scan Previous Track Item(Local ): Usage, data= [ 0xe2 ] 226 Mute Item(Global): Report Count, data= [ 0x08 ] 8 Item(Global): Report Size, data= [ 0x01 ] 1 Item(Main ): Input, data= [ 0x02 ] 2 Data Variable Absolute No_Wrap Linear Preferred_State No_Null_Position Non_Volatile Bitfield Item(Global): Usage Page, data= [ 0x0b ] 11 Telephony Item(Global): Report Count, data= [ 0x01 ] 1 Item(Local ): Usage, data= [ 0x21 ] 33 Flash Item(Main ): Input, data= [ 0x02 ] 2 Data Variable Absolute No_Wrap Linear Preferred_State No_Null_Position Non_Volatile Bitfield Item(Global): Report Count, data= [ 0x07 ] 7 Item(Main ): Input, data= [ 0x05 ] 5 Constant Array Relative No_Wrap Linear Preferred_State No_Null_Position Non_Volatile Bitfield Item(Main ): End Collection, data=none Endpoint Descriptor: bLength 7 bDescriptorType 5 bEndpointAddress 0x82 EP 2 IN bmAttributes 3 Transfer Type Interrupt Synch Type None Usage Type Data wMaxPacketSize 0x0010 1x 16 bytes bInterval 1 Device Qualifier (for other device speed): bLength 10 bDescriptorType 6 bcdUSB 2.01 bDeviceClass 239 Miscellaneous Device bDeviceSubClass 2 ? bDeviceProtocol 1 Interface Association bMaxPacketSize0 64 bNumConfigurations 4 Device Status: 0x0000 (Bus Powered) Hardware controls don't seem to influence the noise in any way, or I wasn't able to find a pattern. Plugging out all the other usb devices (keyboard, mouse, gigabit ethernet card) doesn't help. Changing sndiod buffers changes the pitch of the noise, but doesn't help.
