I have a new Fender "Sting" bass. I have had it about a week. It sounds fantastic. Every so often ,while holding the bass in normal playing position ,hands on bass, I will notice a little quick "creak" or "pop" sound. It seems to be coming from the neck. It seems to stay in tune after this happens. The neck screws are tight. I can't seem to see the neck move, which is probably good. Is this normal? Maybe a string hanging up on the nut? Should I take it back to GC and just get a refund?