Basically the title is exactly my problem...
I had the Phatbox installed in my 2000 S4 for a year... Had ZERO issues with it after install (well, except when I tried to do a firmware update but, thanks to this forum, that was fixed in a few hours)... Sound output from the Phatbox was perfect... Everything was fine...
I recently bought a new S4 and I installed the phatbox into this car (thanks to a few do-it-yourself links posted on Audiworld) and got the Phatbox working...
Everything seems to be fine, Changed the Stereo Type to "O" and we were up and running... Played a song and it seems like the volume was WAAAAAAAY low, with a very faint sign of bass... So I burned a CD from the music I have on the DMS, and compared the output from both the Phatbox and the CD... Phatbox sound output is not accurate, and the exact same song, from the MP3 has little to no bass... I tried adjusting the EQ with no luck... I removed the stereo and checked all connections, triple checked with instructions I had for wiring the phatbox into my car and everything was good...
Anyone have ANY idea what this can be?