Brake and CD changer problems

[asumaj]

I have a 2001 Jetta with which I've had no problems in the past (other than the windows falling down repeatedly, old news to most). Last month I drove from Connecticut to Minnesota and had no serious problems in the first 14-hour day of driving. I say no "serious" problems because at some point, the CD changer in the trunk stopped working. Initially, I got the "Check Magazine" error, which I have seen many times before, but after numerous startings and stoppings of the engine, it was never resolved, and in fact, morphed into a "CD Error" message. Still, I was miffed but unconcerned.

The next morning, I drove for about 5 hours before the first stop, then did some stop-and-go driving for another 30 minutes, at which point the ABS light came on with a beep, and the Brake light started flashing. After a quick check into the manual which informed me to pull over immediately as the brakes may suddenly lock up, I found a place to stop, restarted the car, and had no further problem for the remaining 4 hours of the trip.

2 days later, during some in-town driving, the light came on again, and, after pausing briefly after I restarted my car, remained on for the rest of my 15-minute trip home.

I made an appointment with a dealership 110 miles from where I was staying (the nearest VW dealer to northern Minnesota, no wonder they all drive American cars up there!) before I returned home. They told me that the ABS sensor seemed to be malfunctioning, since the ABS worked fine once they reset the error code. They suggested I watch it carefully on my way home, and report and further problems to my local dealer, or have it replaced by them for $500 that day if I was concerned about it. Furthermore, the CD changer was "shot," and would be just a little under $500 to replace. I decided to hold off on the repairs until I got home.

The car went without incident until the 2nd day of my trip back East. Again, following a 16-hour day of driving, the ABS and brake lights both came on the next day, after 2 hours of brief excursions. This time, when I shut off and exited the car, I heard a whining/humming sound coming from the direction of the right rear tire well. It stopped quickly, as though it was resonating from my having slammed the passenger side door. Curious, I closed the door again with the same result. I repeated this action 4 times, and the 5th time, the noise continued for 5 minutes. I started the car, set and released the hand brake, drove in reverse and in forward again, and the noise finally stopped when I turned off the engine. Up to this point, I was willing to write off my problems to simple "VW workmanship," but now I started to worry.

15 minutes later I started my return trip from upstate NY to CT. The lights came on within 30 seconds. I drove to a gas station 15 minutes away, refueled, and the lights did not come back on. That is, until I had driven for another 4 hours and got off the highway to rest. After my break, the lights came on again, and could not be quieted. I drove through 3 states basking in their glow, until, finally, I stopped once more, restarted the car, and drove the rest of the trip uneventfully.

In the 2 weeks that I've been home, the lights have come on twice, both times not being extinguished by my restarting the car. So far, I have not noted ANY mechanical problems with the car, other than the CD changer not working. Any thoughts?