Bug 209921

Sorry for the double post, here is the pulseaudio error:
```
● pulseaudio.service - Sound Service
     Loaded: loaded (/usr/lib/systemd/user/pulseaudio.service; disabled; vendor preset: enabled)
     Active: active (running) since Wed 2020-10-28 19:20:15 CET; 35min ago
TriggeredBy: ● pulseaudio.socket
   Main PID: 1272 (pulseaudio)
     CGroup: /user.slice/user-1000.slice/user@1000.service/pulseaudio.service
             ├─1272 /usr/bin/pulseaudio --daemonize=no --log-target=journal
             └─1396 /usr/lib/pulse/gsettings-helper

d’oct. 28 19:20:14 asus-arch-icar systemd[1074]: Starting Sound Service...
d’oct. 28 19:20:15 asus-arch-icar pulseaudio[1272]: Constant volume 100 configured for element 'Master', but the available range is from 0 to 87.
d’oct. 28 19:20:15 asus-arch-icar pulseaudio[1272]: Constant volume 100 configured for element 'Master', but the available range is from 0 to 87.
d’oct. 28 19:20:15 asus-arch-icar pulseaudio[1272]: Constant volume 100 configured for element 'Master', but the available range is from 0 to 87.
d’oct. 28 19:20:15 asus-arch-icar pulseaudio[1272]: Constant volume 100 configured for element 'Master', but the available range is from 0 to 87.
d’oct. 28 19:20:15 asus-arch-icar pulseaudio[1272]: Constant volume 100 configured for element 'Master', but the available range is from 0 to 87.
d’oct. 28 19:20:15 asus-arch-icar systemd[1074]: Started Sound Service.
d’oct. 28 19:25:04 asus-arch-icar pulseaudio[1272]: ALSA woke us up to write new data to the device, but there was actually nothing to write.
d’oct. 28 19:25:04 asus-arch-icar pulseaudio[1272]: Most likely this is a bug in the ALSA driver 'snd_hda_intel'. Please report this issue to the ALSA developers.
d’oct. 28 19:25:04 asus-arch-icar pulseaudio[1272]: We were woken up with POLLOUT set -- however a subsequent snd_pcm_avail() returned 0 or another value < min_avail.
```

Created attachment 297477 [details]
alsa-info output from 5.13.0-rc4 (no model option set)

I come from here https://bugzilla.kernel.org/show_bug.cgi?id=212547 (Bug about the no volume control in back speakers in the same laptop) where you point out this issue that also affects me, and as you requested there (https://bugzilla.kernel.org/show_bug.cgi?id=212547#c10), i tested some model options to see if there is a change of the Mic behaviour.

First, pointing out: The laptop have a combo headphone/mic plug, and the default behaviour is it only detect and use the built-in mic, whatever a headset with mic is plugged in or not. (btw, the built-in mic seems to record with a surprising good quality).

Model options tested: 

* asus-zenbook: no sound recording with or without a headset plug in (No mic works).
* asus-zenbook-ux31a: no sound recording with or without a headset plug in (No mic works).
* headset-mic: Only detects and work the built-in mic, being the headset plug in or not (like default).
* headset-mode: Only detects and work the built-in mic, being the headset plug in or not (like default).
* alc283-sense-combo: Only detects and work the built-in mic, being the headset plug in or not (like default).
* asus-g73jw: Only detects and work the built-in mic, being the headset plug in or not (like default).
* alc294-lenovo-mic: Only detects and work the built-in mic, being the headset plug in or not (like default).
* asus-x101: no sound recording with or without a headset plugged in (No mic works), but appears in alsamixer and a menu mic selection in KDE audio settings, INTERNAL and HEADSET, but it default to INTERNAL always whatever the headset is plugged or not. Also it doesn't use the headset speakers when it is plugged in (built-in speakers are used).
* alc298-spk-volume: Appears again the menu selection (INTERNAL and HEADSET) when the headset is plugged in, defaulting always to INTERNAL, and INTERNAL (Built-In Mic) works, but when is selected HEADSET there isn't any sound. Also this option affect to the built-in speakers (it only use the front ones) so this is not useful.
* dell-headset-multi: Appears the menu selection again when the headset is plugged in, this time with INTERNAL, MICROPHONE and HEADSET. MICROPHONE doesn't record any sound, but INTERNAL record the Built-in Mic, and HEADSET the Headset mic. It doesn't auto-change when the headset is plugged in, it always default to INTERNAL (you can change to HEADSET manually).

I can test more, but at this moment the dell-headset-multi option model is the better one because at least made the headset mic to work, although you need to select it manually. This option could be if there isn't a MICROPHONE selection (it doesn't do anything), and if the mic changes to HEADSET automatically when the headset is plugged in, however, i think it's better to keep the option to select the mic useful because (A) i don't know if a headset without mic could be detected as with mic, making impossible to use a mic with normal headphones, and (B) like i said the built-in mic seems pretty good and mostly i will use that one rather than a headset built-in which normally are pretty cheap and poor.