Danielk,
That's a fair question. No. The room is on a dedicated circuit, but the audio system shares through a modest Monster line conditioner, the $400 one. I've made some overall improvements to the system by upgrading power cords, adding the line conditioner, upgrading cables, etc, but the deficiency I'm experiencing sounds to me a while lot like the amp is running out of steam. It's a 1999 vintage Musical Fidelity Amp which is rated at 120 watts. Within a year, I may even build up enough diplomacy points with my wife so that I can do some moderate construction to create a much better "audio" room. That room will certainly have the requisit AC power specs.
My preamp, btw is an Audio Research SP16 which may also be a weakish link in the chain; although, not awful by any stretch.
Peter