Headphone jack volume on ALC287 (Thinkpad X1 extreme gen 5) is too low unless the speaker channel's volume is past a certain threshold.

[GitHub issues - edited <github@xxxxxxxxxxxxxxxx>]

alsa-project/alsa-ucm-conf issue #298 was edited from Noted-Jrelvas:

First of all, apologies for the verbose title.

I've ran into a very interesting issue with my Thinkpad X1 extreme gen 5's audio. For whatever reason, the headphone jack's sound output is very quiet unless I raise the speaker channel's volume past a certain threshold.

The headphone jack sounds very quiet...
![image](https://user-images.githubusercontent.com/55360900/228303084-57945125-59ba-4daf-befb-bb9e18b6f491.png)

...but raising the speaker channel's volume fixes the issue:
![image](https://user-images.githubusercontent.com/55360900/228303657-30efa3c3-2965-4b3b-a870-b4ae6e803aba.png)

I suggest automatically setting the speaker channel's volume to 100% when the headphones are plugged in and restoring it to its original volume once they're plugged out.

Here's the output given by `alsa-info.sh`:
http://alsa-project.org/db/?f=21904435b29e0eb23d2d0b30bbabe15734df7ad7

Issue URL     : https://github.com/alsa-project/alsa-ucm-conf/issues/298
Repository URL: https://github.com/alsa-project/alsa-ucm-conf