"Channel volume" partially reset after pausing and unpausing audio in Chromium

Using pipewire 0.3.13 with the pulseaudio compat and Chromium 85.0.4183.121 and some stereo headphones on Arch Linux

This is the most of a reproduction I can provide, it happened a couple of times today but I can't reproduce it with exactly these instructions - I'll update when I know more.

Start audio stream (tested with music.youtube.com) in Chromium
Adjust volume of playback with pavucontrol (e.g. to 15%)
Pause audio stream for a few minutes(?)
Resume audio stream
Notice that the left channel is still at the original volume (15%) while the right channel reset to 100%. (To see that in pavucontrol you have to disable the "Lock channels together" option.)