Hi Bastien, On 12/10/16 07:10, Bastien Nocera wrote: > Hey, > > I recently bought some cheap USB soundcards for a computer that doesn't > have any audio output other than through the HDMI output, and the > screen I'm attaching doesn't have an audio output. > > So I'm looking to plug in 2 of those USB soundcards, and switch between > them depending on whether I'm using headphones, or want to use the > standalone speaker. > > Obviously, it would be so much nicer if I didn't have to switch between > the outputs by hand, and ignored the "headphones" sound card when not > plugged in. > > My questions are: > - does the USB audio driver support jack sensing? > - is this something standard that's just not implemented yet? In which > case, I'd be up for at least trying, given specs. > - or is it something that depends on the device, and in which case, how > would I find out?
What you need is PulseAudio server instead. PulseAudio supports this via kcontrol for quite some time. Jack is supposed to be a low-latency audio server for audio applications, not for normal desktop usage. > > Some details about the device itself below. > > Cheers > > /proc/asound/cards: > 4 [Device ]: USB-Audio - USB Audio Device > GeneralPlus USB Audio Device at usb-0000:00:14.0-9, > full speed > > $ amixer -c 4 > Simple mixer control 'Speaker',0 > Capabilities: pvolume pswitch pswitch-joined > Playback channels: Front Left - Front Right > Limits: Playback 0 - 30 > Mono: > Front Left: Playback 16 [53%] [-21.00dB] [on] > Front Right: Playback 16 [53%] [-21.00dB] [on] > Simple mixer control 'Mic',0 > Capabilities: pvolume pvolume-joined cvolume cvolume-joined pswitch > pswitch-joined cswitch cswitch-joined > Playback channels: Mono > Capture channels: Mono > Limits: Playback 0 - 14 Capture 0 - 30 > Mono: Playback 1 [7%] [-10.50dB] [off] Capture 26 [87%] [27.00dB] > [on] > Simple mixer control 'Auto Gain Control',0 > Capabilities: pswitch pswitch-joined > Playback channels: Mono > Mono: Playback [off] > -- > To unsubscribe from this list: send the line "unsubscribe linux-usb" in > the body of a message to majord...@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- Felipe