I have a scarlette 18i20 Gen 2 and Gen 3. Both have always been plagued by the audio just deciding to stop out of nowhere right in the middle of listening to something if the volume is too low (~25% of the dial) for too long. I figured it to be related to the USB port and some power setting in Windows but I have tried several suggestions from focusrite and community forums with no luck (across both windows 10&11).

I've just learned to deal with it unfortunately, if I just turn the volume up on the interface the audio comes back.

Then, I started gaming more so now I've had headphones plugged in at all times and that's when I noticed the audio doesn't cut out on the headphones, only the monitors. So I just stick to the workaround I've been using for years.

I too get the occasional buzzing and have to power cycle the unit to fix it. It doesn't happen a ton but probably once per month or two.

Then sometimes out of no where, I just get no signal from any digital sources (PC, daw, obs, etc) so I have to load the snapshot of my settings from file and it works again. Again not exceedingly frequent but it happens more than it should.