I've had the F90bt installed for about 6 months in my car, with the SCC1 Sirius Tuner + Pioneer CD-SB10 Sirius interface. The sound quality to me has always seemed subpar only on the Sirius. I also have HD Radio and iPOD which are both beautiful in terms of sound quality. But then when I switch on the Sirius, it seems as if the audio is terribly compressed with a low bitrate, alot of hissing occurs on high notes and lows are very muddy. I've tried making adjustments with the equalizer and other sound system settings in the radio, but it just doesn't do much to brighten up the poor quality com