Amp problem, wahoo!

Bidley

So I just had a quick jam through my Carvin X100B reissue head, and noticed that the clean channel sounds horrible. There's a fair bit of distortion, and not to good kind. It's more like crackly interference. You can just about hear the crackling when it's idle, and it still makes the sound with multiple guitars, as well as when it's plugged straight into the amp, no pedals in front or in the loop. It also makes a massive wooshy crackly noise when I switch it onto standby and power it off. So what do we reckon? Valves?

ICBM

Possibly. Do any of them look funny when it's making bad noises?

[/scientific analysis]

Bidley

I just switched it on to check, and now it sounds fine! Which is annoying... I remember having a look earlier though, and I don't remember seeing anything out of the ordinary, but I can't be sure.

ecc83

If it is practical AND SAFE! to do so, arrange a mate to play the amp and tap each valve in turn gently with a pencil.

Note, this could result in a seriously loud blast of noise so be prepared to dive for the off switch!

Dave.