well checked out the power amp; channel A had no volume, no noise, until the gain was maxed, and it was very low.
It could be a loose or bad power tube, or something more serious.
The GC manager wasn't in the store, and I asked the associate if we can take the cover off and check the tubes, to be sure the tubes are not loose and if it didn't help, we could swap the channel B tubes (channel B worked) into channel A...he said we don't touch anything with tubes. I said well, if it's a loose or bad tube, and it works I'll take it; if it's something more serious, then I'd want to return it.
He said the manager will be in the store this morning and to call the store in the morning. So as soon as the store opened, I called and spoke to the manager. I asked if he would check for loose or damaged tubes / swap the channel B tubes, and he said I already refunded your purchase (before the store opened). So, I left it at that.
My luck it would be the channel A output transformer...not worth the risk; but at least try checking the tubes!?