My amp was sounding like crap.  I cleaned and check all connections and nothing seemed to help.  Then I cleaned out the volume pot with contact cleaner and viola!
I don't think the amp sounds quite as good as it used to.  Or, maybe I've just lost confidence in the volume pot.  It has to go.
I'm considering switching to a stepped attenuator.  Any suggestions?  I hope Steve chimes in here!
KD White