Did you drive the car with vacuum disconnected? There is a plate in the distributor that the pick up rides on. It rotates around as the vacuum actuates it. If the wires are broken there is a possibility that you could have an intermittant connection to the ignition pick up. I have also had to replace the short harness connector on the outside of the distributor because it was intermittant. This is an area where these wires are subjected to some pretty severe temperatures from the turbo.
Long story short. If you disconnect vacuum and drive the car and the problem is gone, then the above described problem could very well be there. Since vacuum is not there and the plate and wires are not moving then the connection has a better chance of staying constant.
The next thing to be suspicious of might be the CD box. I however dont know if that is something that responds like this or if it just quits working. I have never (Knock on wood) had a problem with mine.
Let me know if this helps. Im sure I can think of some more things to look at.
.................................................. ...C
