by Geek » Mon Apr 24, 2017 1:08 pm
Hi,
That's a common sound in olllllld tube rigs, but not new ones.
I'd look first for a bum solder joint, especially around the tube socket. Also re-dress the socket pins (make them tighter).
Failing that, look for perhaps a defective resistor.
Bad resisitors and leaky caps are usually the cause in vintage equipment, but when it's something new, procedures have to change a bit.
Cheers!
-= Gregg =-
Fine wine comes in glass bottles, not plastic sacks. Therefore the finer electrons are also found in glass bottles.