Hi guys,

I was playing just now and all of a sudden started to get a crackling sound and a low hum.. I looked to the back of the amp to see if any of the tubes wern't lit, etc... They were all lit, with two glowing bright orange and the other two not.. There was a hint of blue in the two that were glowing too.

I tried changing guitar cables but that didn't help.

Do you have any ideas?
dead tubes. and if you keep going itll blow the fuse or v seriously damage the amp
so go get some new tubes