I have the same problem, no cartridge, or skipping while driving, then it stops all together, removing the cartridge and put it back in will help for a short period of time , then the trouble starts again. I am going to take it out, and see if I can get it serviced. As soon I have done that I can post on how to get it out. I did found a used one on EBay for $ 395.00 For a USED one? which probable ends up with the same problem. The next alternative would be to replace the changer with a non Mercedes one, those new changers are so much better in technology then the ones who are like 10 years old. I checked with crutchfield, (check out there web site) and they do have one whereas you don't need to revamp the wires, considering that the changer runs trough fiber optics cables, it's just plug and play, I just need to check the dimensions of the changer, I would like to install it in the same location as the one I have now. Don't know about the price yet either, but I will find out.