Bass speakers not working on Lenovo Yoga Pro 9 14IRP8, Ubuntu 22.04

Question 1

Folks, I have recently purchased this laptop: https://psref.lenovo.com/Product/Yoga/Yoga_Pro_9_14IRP8

And I can only get the front speakers working on Ubuntu 22.04 which results in the sound being not great to say the least.

From reading around I found out that the laptop comes with two sets of speakers like many new Yoga laptops and both of them are supposed to be playing at the same time: https://bugs.launchpad.net/ubuntu/+source/alsa-driver/+bug/1926165

Same issue on Fedora: https://discussion.fedoraproject.org/t/problem-with-sound-on-new-lenovo-laptops/72456

I was not able to get the speakers running with the tricks above, does anyone have an idea? Thank you in advance.

I am currently running the kernel: 6.2.0-33-generic.

Question 2

I was able to get the bass speakers working on a Yoga pro 9 14IRP8 with Pop OS 22.04.

I followed this comment :

Install i2c-tools :
```
sudo apt install i2c-tools
```
Get the i2c-bus number on which the TIAS2781 component is connected. I don't know how to do that. I tried the fix with 0 and it didn't work, but it worked with 1. Use at your own risks.
Download this script and run it as sudo :
```
sudo bash ./2pa-byps.sh 1
```
where you replace 1 by the bus number that works for you.

Your subwoofers should work at this point. You need to run the script after each reboot, personally I added it to my root's cron.

The only remaining problem is that the system volume doesn't control the applications volume, so I have to set each app volume from the sound settings (same problem as here). It's annoying but it's better than having no bass.

EDIT 1: Use ls -l /sys/bus/i2c/devices/ to get the bus number (cf @pierolefou's comment). EDIT 2: Looks like the fix is not necessary anymore with kernel 6.8; but I wasn't to get the bass working with kernel 6.9 (with or without the fix).