There are three things,
One is a ground loop, use an adapter to lift the ground pin of the electrical cord.
use an adapter, do not cut the ground pin off the power cord.
Two is an actual blown transistor inside the unit
Three is a broken input connector, damaged circuit board where the input is.
Does it hum with the input unplugged?
Thanks for the suggestions.
Ground loop idea: the power chord does not have a third pin and each prong on the plug is the same width. I rotated the plug but it made no difference. Also a newer Kenwood plugged into the same outlet and connected to the same speakers has zero buzz.
answer to "Does it hum with the input unplugged?" If by inputs you mean other components connected to the amp, yes, it buzzes equally whether a turntable or CD are connected or not. If you just connect the amp to the speakers with nothing else in the room running and nothing connected to the amp, it buzzes the same. Also as I mentioned above, I plugged the amp into the same electrical outlet, and connected it to the same speakers as a newer Kenwood (which has no buzz), and the Sansui still buzzed. Maybe I should take it to a repair shop to check for internal problems? or are there things I can still try here.
Thanks again for your help...Art