My car has a B&M shifter installed by the previous owner. It was quiet for the first few months, but it has developed an irritating rattle from vibration above 2,500 rpm. I pulled up the console and found that the four allen bolts on the shifter were really loose. So I put some thread lock on the bolts and it was quiet for about six weeks (except for 3rd above 2,500) and now it has returned. Any ideas?