sigh, i figured the fx would have this problem too ( had it for barely 2 weeks ).. on my g35 coupe which i sold, there is a common problem with the radio and a/c on 'the 03 and '04 models.. a/c would suddenly go on full blast and radio controls wouldn't work ( infiniti changed the radio on the '05 onwards ).. problem was that the a/c and radio share the same circuit board.. only solution was to have the whole radio replaced / repaired.. that or a good whack on the side of the console.. when i had mine replaced, i stopped using the cd and just used the iPod intergration i had installed.. no problem since..