XM now sounds worse

I've recently noticed that when listening to XM Radio, the sound on XM Classics and some other stations is thin, distorted slightly on the high end. I think that while the sound has'nt always been great, it used to sound better than this. I can't figure if it's my system or XM has lowered sound quality by adding more stations.

My setup is kinda strange: The Polk XM Tuner is hooked to a Ramsey FM100 FM Transmitter to brodcast (thru my house only) to my various tuners. Now I do know that this is an 'extra processing step' - but this USED to sound great. Could Lightning possibly mess up the sound in the Polk Tuner without totally frying it? It does'nt make any sense because it used to sound good. I have several different systems in my home, and receiving XM in this manner NOW sounds bad in All my various systems, whereas it used to sound good. So I don't think it is a bad receiving tuner, or the fact I have too much equipment plugged in - like I said it used to sound good, but now....

Any thoughts would be appreciated.