my amp has been having these odd drops in gain and volume randomly lately. it'll disappear and then come back without warning. i have my chain set up EQ -> OD -> amp. would it be a battery issue or more likely the tubes are getting old? i got this amp used about 6 months ago so i have no idea how much use the tubes had beforehand. if so, is it more likely to be the pre or power amp tubes?
could be the tubes, or possibly the cables and/or batteries. mess around with all of those
Check your cables before anything. If they all seem fine, then it's time to swap your tubes. You never know how much wear and tear the tubes have gone through if you bought a floor model.
That randomly happens on my amp too.
But it's because I need to clean the pots.
Really, It'll be in one position for volume, then all of the sudden the volume will drop.
I just end up needing to turn it a little bit then turn the knob back and it's back to normal.