R600 problem/question

[The boa]

So I have been playing through a series 1 carvin r600 for quite a while now. It's a great and versatile amp, but recently has been having issues.

The noise gate seems to come on unexpectedly after I have been running the amp for a while. It doesn't do it all the time, but after about an hour of playing the gate just pops on and cuts off all sound. If I turn it off for a second then back on it comes back, but obviously this is a problem for gigs.

Anyone have any idea what may cause this?

 

[BassmanPaul]

The amp getting too hot? What speakers are you using and their impedance?

 

[The boa]

250w @ 4 ohm ashdown 2x10 for practice. That's the only cab I have had this issue occur while using. It doesn't seem to be getting too hot, but it's hard to tell since it's in a small rack box.

 

[BassmanPaul]

Is the amp fan cooled? I had a used Peavey Mark VI that did the same thing. On opening the amp up the inside was completely clogged with dust and other crap. A good vacuum out aided by a soft paint brush got it all out. That cured the problem. Not saying that this will cure your ills but it’s worth a look.