Increasing a tracks Max Gain (from the Shift + A menu) mutes track audio. To unmute the track you have to decrease Max Gain. So basically if you want to increase the gain of a track you first have to turn max gain up and then turn it down on step to get the track audio back.
This is on the 2021-12-24 Update.
I noticed something similar as well, but I noticed that it would only mute the tracks audio if I didn’t hit enter after adjusting the gain. I also noticed it doesn’t seem to want to preview the gain adjustment as I’m increasing it, I’m not sure its supposed to, but I think it did it in the firmware before this one. It seems like it previewing worked ok while decreasing gain. I only got play around with it for a minute when I discovered it and haven’t been able to revisit it, so take that with a grain of salt.
I got the same issue on update 2021-12-24. It was not there before. Same steps to reproduce as you described. Thanks for flagging it. I use this function on almost all my projects.
Thanks for the report. Fixed in dev.