Audio cracking PS1 games

Hey guys,

I am noticing slight but very distracting audio crackling with PS1 games on my MM+. Tried messing around with different sound settings, but nothing helped so far. Any idea how to fix this? My CPU clock is running already at 1950 with my cpuclock.txt I'm on a sandisk micro sd, not the stock one. Also I am running the latest Onion Os. This is the only system so far with these audio issues.

Any ideas much appreciated :)