This has happened twice now. While working on a project, the master volume and mute buttons stop responding. Most of the loops volumes are in the red and I can't change it.
I was dragging and dropping loops into tracks(the tracks had loops in them already... I dropped them at the end beyond the end marker). When I found the sounds I wanted I created new tracks and dragged each one into their own track... that's when the controls broke.
But it gets worse, I made two copies of a file to try different arrangements without altering the original and both files are broken but the original was fine. Unfortunately one of the files that broke was one I planned on keeping. Restartng and rebooting didn't help.
I'm using MMM 2020 version 29.0.6.35, windows 10. Not using an audio card, just the on board sound.