Lifted grounds- No more FM distortion on Tuner

I just realized that my FM reception is 100% perfect now. I recently got a pair of Rogue M120 Magnum Monoblocs and lifted their grounds. The Tuner and the pre is grounded. Prior to this upgrade the Tuner would have lousy FM reception and would get better in the late evening. Before the upgrade my integraded and all other components were grounded. Was I getting a ground loop which was affecting my Tuner reception? Why did this happen? What causes the ground loop?
That is weird! I always tell people that are "happy" with there systems to try and float the ground, sometimes it makes a huge improvement. Then again sometimes it does very bad things, if nothing else its a lesson for others to head out to the Home Depot and pick up a whole lot of Ground Cheaters and spend an evening "floating" the ground, see what happens you might be surprised.
Glad to here you have some nice improvements with your system Eric.

Buckingham, stranger things have been known to happen. Just be glad that you were able to get the problem resolved.

By the way, have you tried grounding the amps and lifting the preamp, tuner and other sources ? Some say this works better, but i think that it is very system and component dependent. Sean
What you can also try now that you have removed the ground, is to flip the plug back and forth (reverse the AC polarity) and see which way sounds better.
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The Blue Circle BC63 and BC64 cords have two switches. One lifts the ground and the other reverses the polarity. Great for testing lines and equipment, or just for tweeking.
Make sure the unit is grounded some how. Lifting the ground on the plug can be very dangerous since the chassis becomes hot if the unit should fail, leading to potential nasties. I believe the proper way is to use a balanced transformer to stop ground loops. Another neat way is to use input transformers on the RCA jacks, a la Rowland. I won't deny the potential benefit of using cheater plugs since I have but don't now since my health is not worth any incremental benefit (ALL sonic benefits being incremental when I speak of my health). There was a healthy discussion on this on Audio Asylum and that's where I decided to prevent future shock, as it were, and plug 'em all in as should be done...