Adjusting volume only affects the right channel

I am using a Yoga Slim 7 Pro, with a Ryzen 5 5600H (not U, which seems to be more common). Pretty much everything else works perfectly so this is driving me mad. Currently on kernel 6.0.8-zen1-1-zen. I’ve tried other kernels, ubuntu, fedora and pop-os but they all have the same problem. I currently use the default pipewire setup.

In a nutshell:
When I adjust my speaker volume (through gnome or kde), the right speaker is adjusted as expected but the left speaker always stays on full volume until I drop the volume to 0. I assume volume 0 just mutes all sound?

I have managed to “fix” this in the following ways so far:

  1. Setting the device profile to “Pro-audio” from pavucontrol. If I want the channels to stay in sync I have to first set the volume to the max. For some reason at boot volume is adjusted to ~70% so the speakers are allways a bit off balance.
  2. Adjusting the “PCM” slider in alsamixer instead of the master volume. This works but I have no way of controlling it through the integrated volume buttons or the DE.

Here’s pactl info:

➜  ~ pactl info
Server String: /run/user/1000/pulse/native
Library Protocol Version: 35
Server Protocol Version: 35
Is Local: yes
Client Index: 4429
Tile Size: 65472
User Name: eea
Host Name: yoga-slim-7-pro
Server Name: PulseAudio (on PipeWire 0.3.57)
Server Version: 15.0.0
Default Sample Specification: float32le 2ch 48000Hz
Default Channel Map: front-left,front-right
Default Sink: alsa_output.pci-0000_03_00.6.analog-stereo
Default Source: alsa_input.pci-0000_03_00.6.analog-stereo
Cookie: 8eba:0b9c

Here’s alsactl info:

➜  ~ alsactl info
#
# Sound card
#
- card: 1
  id: Generic
  name: HD-Audio Generic
  longname: HD-Audio Generic at 0xfd3c8000 irq 71
  driver_name: HDA-Intel
  mixer_name: ATI R6xx HDMI
  components: HDA:1002aa01,00aa0100,00100700
  controls_count: 14
  pcm:
    - stream: PLAYBACK
      devices:
        - device: 3
          id: HDMI 0
          name: HDMI 0
          subdevices:
            - subdevice: 0
              name: subdevice #0
        - device: 7
          id: HDMI 1
          name: HDMI 1
          subdevices:
            - subdevice: 0
              name: subdevice #0
  hwdep:
    - device: 0
      id: HDA Codec 0
      name: HDA Codec 0
      iface: 16
#
# Sound card
#
- card: 2
  id: Generic_1
  name: HD-Audio Generic
  longname: HD-Audio Generic at 0xfd3c0000 irq 72
  driver_name: HDA-Intel
  mixer_name: Realtek ALC287
  components: HDA:10ec0287,17aa384f,00100002
  controls_count: 18
  pcm:
    - stream: PLAYBACK
      devices:
        - device: 0
          id: ALC287 Analog
          name: ALC287 Analog
          subdevices:
            - subdevice: 0
              name: subdevice #0
    - stream: CAPTURE
      devices:
        - device: 0
          id: ALC287 Analog
          name: ALC287 Analog
          subdevices:
            - subdevice: 0
              name: subdevice #0
  hwdep:
    - device: 0
      id: HDA Codec 0
      name: HDA Codec 0
      iface: 16

And here’s a screenshot of alsamixer:
kuva