Light switch and amp

You got good sound that night because the power grid is less noisy in the middle of the night. The noise you are hearing through the light switch could be coming through any component power cord. If you buy some power conditioner or power regenerator like PS audio, plug your gear into that except for your amp. Plug your amp direct in the wall. Eliminate any cheap power strips.

circuit for amp receptacle and light switch may be tied together & picking up backfeed

Yeah I been kind of looking into a conditioner. Its a little scary for someone new to this to spend money on one. So many people think they don't work or do very little.

Really how much do I spend to get one that works? Maybe through music direct so I can return it?

I really just can't get the soundsage right in my room. The soundstage just appreared one night. It was very layered and sound amazing. The amp has great reviews and if I could get the layering and soundstage back I would be in so happy.

I thinking about trying other outlets and another rooms. My current room is small and has a bed a lot of things in it hoping to use another rooms as see if that works.

Get a power regenerator or a very good AC power filter. Your amp might only see semi-clean power for limited times during a day but with a regenerator it can sound its best all the time.

I use the PS Audio P3 Power Plant in my system and it works wonderfully to supply clean power to my entire system.