On Tue, 30 Oct 2018 19:45:36 +0100, Mutz Heuer wrote: > > I checked the source code of quirks-table.h on branch 4.19-rc8. It's too old :) Linus git tree already contains more fixes, and the corresponding one is commit c369c8db15d51fa175d2ba85928f79d16af6b562 Takashi > It still > contains the problematic workaround. It doesn't seem to fit any longer to the > headphones current firmware. Checking the 4.15.7 kernel (without the quirk) > works much better. At least the device is shown in the mixer and fixing the > samplerate to 48kHz leads to a useful configuration. To be honest I do not > really understand how to define a fixed table for supported sample rate > without fiddling with other parameters. The HID seems to working too. At least > I am able to use the headphone buttons to in/decrease the volume and to stop > and restart playback. The microphone is not shown - but that does not seem to > work on windows either - as far as I understand the orginal patch to support > the headphones. > > With the qurik in place I get no really helpful error messages ... > > I hope that helps to clarify the situation, > > Mutz > > Takashi Iwai <tiwai@xxxxxxx> schrieb am Di., 30. Okt. 2018 um 12:24 Uhr: > > On Sun, 28 Oct 2018 22:00:35 +0100, > Mutz Heuer wrote: > > > > USB-Audio Connection on Bowers & Wilkens PX Bluetooth Headphones started > > working when upgrading kernel from 4.13 to 4.15 series. Then it suddenly > > stopped working again on newer kernels. The bug report has been > generated > > on the latest working mainline kernel 4.15.7. All newer kernels have > some > > usb quirks in place, which should fix the playback sample rates to 48 > kHz. > > The quirk seems not to be working correctly - it seems to hinder the > audio > > system to recognize the USB-device as a sound device. > > > > The Headphones work on kernels before 4,15.7 when manually configuring > > pulseaudio to a default samplerate of 48 kHz. > > > > PX Headphones are on the newest firmware level. > > > > See https://patchwork.kernel.org/patch/10265345/. Dropping that patch > and > > recompiling the kernel leads to a situation where alsa and pulseaudio > seem > > to to be working again. > > > > Adding > > > > default-sample-rate = 48000 > > > > to /etc/pulse/daemon.conf leads to working headphones. > > > > Maybe the patch has to be adjusted to newer firmware? A quirk seems to > be > > really necessary to avoid the specific patch to daemon.conf. > > > > > > More details can be found in > > https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1773697 > > What would be the best way to proceed? > > Could you check the latest Linus git tree (or for-linus branch of > sound git tree)? The workaround for the buggy firmware was already > included there. Let me know if it still doesn't suffice. > > thanks, > > Takashi > > _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
