I just bought the heads for the used Pearl Session Custom kit I purchased a few weeks ago. I started to tune the 10" tom. I put an Evans G2 on top and as I tuned it to 76 on the dial. One rod is reading 79 and when I get that rod down to 76, it is loose and wobbling. I seated the head before I continued tuning. It's the rod right next to one of the optimount lugs. Pitch actually seems fine from rod to rod. Am I doing something wrong? Bearing edge problem?