Light switch and amp

I have old Exposure XV Super. On one paticular listening session later at night 1100 pm the amp just seemed super sensitive. To the point I could here a small nosie when I turned the light switch on and off in the room through the speakers.

This is has only happen once since I got the amp a month ago. What causes this effect? In this same session the amp was creating a huge sound stage. It almost sounded if the sound was coming from the wall and ceiling behind the speakers.

I have yet to get this affect again. It was really nice and I have not been able to recreate it. Any thoughts?

Thank You
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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.
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
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