Have you tried cleaning all tube sockets, tube pins, fuse end caps and fuse holders? If there are fuses on the PCBs, check with an ohmmeter to confirm that they have near zero resistance. The resistance inside a fuse can occasionally creep up as the joints age. Also, try cleaning the contacts on any detachable cables and ribbon headers inside the unit..
Bad caps???
I have a BAT VK-3ix preamp that I think is having some kind of issue. I got this unit used several years ago and recently I’ve noticed that every now and then the right channel gets distorted. Almost like a radio station just out of tune on an old analog rig. The sound also drops in and out of volume slightly. This only happens for maybe five seconds and generally within the first 10 min of operation. I’ve replaced and swapped tubes around but the sound still persists.
The unit is probably 10 years old by now. Is this what bad caps or going bad caps sound like?
The unit is probably 10 years old by now. Is this what bad caps or going bad caps sound like?