Counterpoint SA 220


I recently purchased a Counterpoint SA 220. It's in very good condition and sounds great... just as I remember my SA 12 sounding.... BUT, I can't get rid of the hum. You think I should replace the tubes? Has anyone had in luck getting these to quiet down?
128x128gbryant
Before taking a recommendation to replace caps try dropping the ground if you have not done so. You can also try your new amp in another system to see if it hums there too. Sometimes it doesn't take much and a sysytem hum can be hard to find.
So far, I have had the best results plugging the SA 220 in with ground and the preamp with the ground lifted.
Do any other components in your system have a ground? If so, try floating the ground on all components exept the preamp.