What areas specifically would you focus on specifically the Dynaco PAM-1 to Quiet the faint hum I have. It is very faint. I have done the caps. It must be lead dressing at this point. Anyone got any ideas? I don't want to give up on them but the PAS2 and 3 I have I cannot even hear when they are on. The PAMs when you walk in the room it is detectable. 60cycle hum. When they are powee on or off I hear it with the power amps on. Not so with my Pas 2 or 3s. What is it??