Frank -- Thanks for the reply. As I'm sure you know, tracking down intermittent "bugs" can drive one a bit wild. I have spent a lot of time on this problem and still have to find some common denominator. IR always is perfect, but RF goes from perfect to useless, and I haven't figured out why. Note that the change happens without any other changes, RF is working - then it isn't - or it may be a bit. When RF isn't working, I may get the first or last digit of the station ID -- or perhaps no response at all. Turning the XRT12 off and back on sometimes fixes the problem -- and sometimes doesen't. I am aware of the reported issues the Polk has when left on for long periods, but that doesn't seem to be the problem here. There is an upgrade to the firmware for the Polk that may help, but getting it may also be problematic. I shall try moving the 6500 and see of that helps!

Craig