My 5150 II has all new tubes that are 2 months old. When I turn on my amp it will be working fine then once it's on for a while the bass just cuts out completely. Mids and High are still there bass is gone. Anyone have any clue what this could be?
Yeah, it's rough. Got a shows coming up. I'm really not trying to have to pay someone to fix it.
Well get it checked out. It could be anything.

I just bought a JSX used a few weeks ago and a screw on tip of a cable had come off and gotten stuck in one of the speaker outputs. Just that little piece touching the circuit board right there would make the volume go really quiet.

If you're comfortable opening your amp up, you can probably figure out what's wrong with it.