punk0mi

My amp is having an odd issue and want to see if any of you have experience anything like it on your own tube amps.

My Ultra Plus head plays great and sounds great at the start. However, after about 10-12 minutes of playing I will hear a slight pop (nothing to punchy, like a subtle pop) and then a constant hum is produced through the cab. When this happens I still get output, with no noticeable drop in volume or gain, just a constant hum.

Sometimes the hum will go away, but most of the time it stays until I cycle the power (turning on standby does not fix the problem).

Anyone else experience anything like that? If so, any ideas what I could try before shipping it off to my repair shop? (Hendrix Sound - takes at least 2 weeks for them to repair anything.)

Thanks.

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