So the truss rod on my '94 Les Paul has always been a little tight. And at one point, I had to take the nut off and put a couple of washers over the threads. A while ago I noticed a small crack, maybe 3/4'' long, right behind the truss rod cavity. Didn't think much of it until the last time I had to tighten the rod to flatten out the neck some. The crack started getting worse, so I backed off. I took it to my local guy, and he seems to think the rod was installed improperly. I've had this bass for about 8-9 years, played it a lot, and never had any real issues. What do you guys think? Seen anything like this? Potential cures???