No sound, no audio profiles, until i do 'killall pulseaudio' (Asus Zenbook 14 UM431D, ALC294 Analog)

[LukasThyWalls]

Hello.

Since i installed KUbuntu 20.10 i have an issue with the audio system. Every time i boot the system, the system audio profiles and devices are not recognized correctly, and normally there isn't an output audio at all and no sound. However, if i do a "killall pulseaudio", suddenly everything appears in the KDE audio profiles and the sound becomes available.

My laptop (Asus Zenbook UM431DA, ALC294 Analog) have 4 speakers: 2 in front (in both sides of the keyboard) and 2 in the back. It have also a HDMI Audio output which is not recognized. But like i said, if i do a "killall pulseaudio" everything appears, including the HDMI audio, and all the expected audio profiles (Stereo, Stereo Duplex, 2.1, 4.0... all with variants with and without input). If i don't do that, all i have is "Off" and "Input Analog".

With the KUbuntu 20.10 LiveUSB (Kernel 5.8.0-25) i didn't have the issue (every boot brings all profiles) but since i installed in the laptop (early installed Kernel was 5.8.0-31) i have the issue. Actually i have kernel 5.8.0-44, the last official one from Ubuntu, and everything is exactly the same.

I tried too using kernels via Ubuntu Mainline Kernel Installer, and i had some differences with newer kernels. I was updating once in a while from there, and at some point, i can be sure, the kernel could bring at boot a different list of available profiles (sometimes only input, other only Stereo, or Stereo + 2.1, or Stereo + 2.1 + 4.0... each one with the input option) and sometimes the HDMI audio appears and sometimes don't. But in all cases, if i do "killall pulseaudio", all profiles come back.
However, Kernel 5.11.4 from mainline was the last one with that behaviour. 5.11.5 do the same as 5.8.0-44, every time at boot the only profiles are "Off" and "Input Analog". Actually i have 5.12.0-051200rc5 with exact the same results.

Using "pasuspender -- aplay -Dplughw:1 example.wav" to bypass PulseAudio gives me sound in every case.

Also i have an issue (maybe related) with ALSA about i can't adjust the volume from back speakers (between 1%~100% are always 100%, between 100%~150% works) and front speakers have a low volume. But it's directly related to ALSA because with pasuspender the behaviour is the same. I reported that here https://bugzilla.kernel.org/show_bug.cgi?id=212547.

I can provide alsa-info and dmesg from 5.8.0-44 (last official one from Ubuntu), but also from 5.8.0-25 (from KUbuntu LiveUSB), and a complete collection of alsa-info, dmesg and image of KDE audio profiles from 5.11.0 (A kernel with the behaviour of different options with every boot). Further, i can add alsa-info before and after "killall pulseaudio", and data from 5.11.4 and 5.11.5, or 5.12.0-051200rc5, which is the last one available in mainline.

Thanks

[LukasThyWalls (thywalls)]

Also i tried to do this https://wiki.ubuntu.com/PulseAudio/Log to make a pulseaudio log from startup, but it doesn't work. Where are the actual right instructions?

[Daniel van Vugt (vanvugt)]

Please try the workarounds mentioned in bug 1897965, or just uninstalling pipewire.

[LukasThyWalls (thywalls)]

I uninstalled pipewire (0.3.10-4) and the profiles are always the ones they should at every boot. I tried to install again pipewire and the "changing profiles at every boot" appeared again. So, it's the source of the issue.

I don't know if it was installed by the base Ubuntu or KDE/Kubuntu, or any program i tested (i don't have any of its inverse dependencies installed) so i will keep it uninstalled, and if is installed in the new (K)Ubuntu version (hirsute) it should be a fixed version (It will install >0.3.24-3, and in the issue you linked it seems it fixed in 0.3.19-3).

Thanks to put me in the right path.