This may sound like I don't know what I'm doing but.... The sound from the CD on my S3 Concert System is cr4p to say the least. On the Radio/tape you can have it a +3 Bass and it sounds good with no distortion. On the CD you need to put Bass at 0, and even then it crackles and distorts. I posted this problem on here a few weeks ago and was told to check the lead to the multichanger in the boot. The connection in the boot is OK so i now need to check behing the HU. I went to Halford and bought the correct tools and tried pulling the stereo out in the ten minutes left in my lunch hour, but couldn't do it. I thought I'd leave it till i got home. On the way home however the stereo didn't even work at all, as though its blown a fuse. I've checked the fuses in the dash, they're ok, i guess there will be a fuse in the back of the HU. - When I can get it out! Are they tricky to get out or have I got a duff stereo thats been messed with before.