I just got back from a short holiday in Budapest (which is AMAZING by the way!), the temperatures were pretty low, hovering around freezing or below most of the time, and i found it really didn't agree with my Canon A-1. When warm it works perfectly, not even a hint of shutter squeak after i sorted it, but after being out in the cold i found the aperture would get stuck at whatever the picture was taken at and sometimes the mirror would get stuck up too. I have 3 different lenses and they all did the same so i know the issue isn't with them. When you advance the film it all resets to how it should be. Was wondering if this is normal or anyone else had experienced similar?