Hi Andrew, Thanks for your feedback. I submitted a new bug on the Apple bug reporter as I could not find out what is wrong here. The problem appears only with inputs (ADC) as playing sound works great (even though the devices are still detected as Headphones…). Dividing all the coming samples in the callback by 28.18 is a dirty workaround, but it did work.
I guess this will be solve in a next iOS release. Best, JC > Le 15 mars 2019 à 20:11, Andrew Smith <[email protected]> a écrit : > > Yes, I found the same thing! > > One thing I did find is that I had some old code that was trying to set the > gain of the input ADC, assuming that the internal mic was being used, and > this got converted to sending out USB HID volume changes, which resulted in > the USB audio device I had connected increasing its gain. When I lowered the > gain I was setting, the USB gain went down as well. > > Seems a little buggy. > > Best, > Andrew Smith > > > > > >> On Mar 15, 2019, at 12:00 PM, [email protected] >> <mailto:[email protected]> wrote: >> >> Send Coreaudio-api mailing list submissions to >> [email protected] <mailto:[email protected]> >> >> To subscribe or unsubscribe via the World Wide Web, visit >> https://lists.apple.com/mailman/listinfo/coreaudio-api >> or, via email, send a message with subject or body 'help' to >> [email protected] >> >> You can reach the person managing the list at >> [email protected] >> >> When replying, please edit your Subject line so it is more specific >> than "Re: Contents of Coreaudio-api digest..." >> >> >> Today's Topics: >> >> 1. iPad Pro USB audio (Jean-Charles Rousset) >> >> >> ---------------------------------------------------------------------- >> >> Message: 1 >> Date: Thu, 14 Mar 2019 21:55:09 +0100 >> From: Jean-Charles Rousset <[email protected]> >> To: [email protected] >> Subject: iPad Pro USB audio >> Message-ID: <[email protected]> >> Content-Type: text/plain; charset=utf-8 >> >> Hi everyone, >> >> I just got the new iPad Pro with the USB-C connector. >> Our iOS app works with different external USB audio devices. >> I wanted to check if everything works fine but I am quite surprised about >> the results I got: >> All USB devices seem to be recognized as « Headsets », not as USB devices >> like it used to be. The number of In an Out channels seems to be correct >> though. >> Furthermore, there seems to be a higher « gain ». I could dig a bit and all >> samples seem to around 28.18 bigger. >> There is very probably a reason about all of this but I have to say that I >> am a bit lost here… >> Note that this is not related to our app as the genuine recorder gives the >> same results. Our audio devices integrate a XMOS, but I also got the same >> results with basic other sound cards. >> Am I missing something? >> Thanks a lot. >> JC >> >> >> >> >> >> >> >> >> >> ------------------------------ >> >> Subject: Digest Footer >> >> _______________________________________________ >> Coreaudio-api mailing list >> [email protected] >> https://lists.apple.com/mailman/listinfo/coreaudio-api >> >> >> ------------------------------ >> >> End of Coreaudio-api Digest, Vol 16, Issue 16 >> ********************************************* > > _______________________________________________ > Do not post admin requests to the list. They will be ignored. > Coreaudio-api mailing list ([email protected]) > Help/Unsubscribe/Update your Subscription: > https://lists.apple.com/mailman/options/coreaudio-api/rousset.jc%40gmail.com > > This email sent to [email protected]
_______________________________________________ Do not post admin requests to the list. They will be ignored. Coreaudio-api mailing list ([email protected]) Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/coreaudio-api/archive%40mail-archive.com This email sent to [email protected]
