Hi Guys I have a well used D 700 that is used for Motorsport. The grip and body would be 4 years old and is in use at tracks every week. Last night at a meeting fps reverted to 5. When I pulled the battery cartridge out and slide it back in all seemed good. Next bracket started at 8 fps but after the initial bust returned to 5. I have tried to clean all contacts with methylated spirits but the same thing happens. Any thoughts or suggestions would be appreciated.