#1
So recently I've been having some amp trouble. Specifically, after about 10 minutes of play my volume starts to cut in and out and sound thin (loses bass in addition). I tapped my tubes and the V1 tube made noise, so I swapped it for another one and now all my tubes make a slight noise when tapped. I wasn't sure if this was bad or not, but it certainly didn't alleviate the volume loss.

My amp has been in and out of the shop for the better part of 5 weeks now, and the tech has sent me elsewhere. (Told me I'll probably need a direct part replacement for a push/pull knob) It's had a tube swap, filter cap replacement, and all the knobs have been thoroughly cleaned. It worked fine for about a week after I first got it back, but after I returned from vacay it's not been the same since...

On a side note, is it normal to get feedback without the guitar plugged in? I just found it a little odd.

Anybody have any idea of what might be wrong?

Summary: Amp has volume issues, and has been in and out of the shop already. Also, can you get feedback without a guitar?
Maximum volume yields maximum goats.
#2
No, it's not normal to get feedback without the guitar. It means one (or more) of your tubes is microphonic. If you've changed every single tube, it means the new ones you got are bad. You should be able to get them replaced for free under warranty, because that's pretty ridiculous.
Kodiak bears make awesome bandmates.

Quote by wolvenrick
no seriously 7x NGD is epicness i declare you the winner of all NGD's on UG never have i seen this xD
#3
All of my tubes I've gotten used... Might new ones address my volume issues?
Maximum volume yields maximum goats.
#4
It's very likely that they would. Like I said, you probably got bad tubes, especially if they were used.
Kodiak bears make awesome bandmates.

Quote by wolvenrick
no seriously 7x NGD is epicness i declare you the winner of all NGD's on UG never have i seen this xD