I have been working on one that is similar, but worse in that it wouldnt play at all till I fiddled with it. I found that a nylon or plastic gear was broken that is part of the shifting mechanism for the pickup. A worm gear would drive the broken gear til it hit the crack and then bind up. A little help with a probe got it through the rough patch, but it is not usable in this condition. This caused a skipping problem, either from song to song, or to repeat sections of the same song. I havent found a replacement gear yet.
Randy, May 2007