Recently acquired a Canon New F1 and there’s a slight problem. When using the camera without a battery, the mechanical shutter works fine, and I’m able to shoot from 1/125-1/2000 just fine. However, with the battery installed, the light meter works fine, the battery check reads fine, but the shutter won’t fire at any speed. Just wondering if it’s an easy fix or if I’ll need to send it out for servicing. Thanks!