Unfortunately, one of the channels cuts out intermittently. Not sure what to look for. But when it works the sound is just wonderful.
The easy things to try first, is cleaning the tube sockets and tube pins with Deoxit, and then the three pots on the front (a little trickier to spray). If cleaning them doesn't cure it, then try replacing the tube with a new one, the 6h30 tube is a dual triode, so maybe one side of the tube is bad. If still happening, then try cleaning the several internal multi pin molex plugs in inside. I suspect there was some oxidation built up after sitting for so long and could just need a good cleaning.
Also, you should try swapping out the 12v battery pack, fresh ones work much better than old ones; and can effect sound quality. They do have a shelf life due date.
Hopefully that does does the trick. If not, then it's time to pull out the multimeter and schematic (if you can find one), or take it to your local service tech to get an assessment.
