I love my 950. I have a GFA7500 into Axiom epic 80 system. I love it. I do get a little hiss, but they say they are working on it. I dont from my seating position, but a buddy that does A/V editing hears it (he cheats, gets like 2 foot from speakers). What did you do to the 545 to modify it. I was considering upgrading caps on the adcom when i got it, but it is so awesome i dont need to!