Had the following odd behavior with my 60D yesterday......
Windy day, so we headed to the beach for some long exposure surf photos (1-1.5 minutes) and flash portrait work. Took the portraits after the surf photos. I used the 10 second timer to give me time to get in position with the hand-held flash with radio trigger, too windy for stands. Frequently, the shutter would release and the flash fire as expected and then begin another 10-second countdown and repeat. More often than not, I had to turn the camera off to get it to stop.
I have ML on that card but was not using any ML features and made sure of it after the first occurence, nor was bracketing set. I did note that ML reported a CMOS temperature of 163 and wondered if the camera internals were hot from the long exposures....it wasn't a particularly hot day, low 80's.
I could not get the behavior to repeat after returning home and there is no feel of a sticky shutter release button, nor was there wind blown sand lodged anywhere.
I'm not overly concerned, as it didn't repeat, but I am curious. Anyone had similar experience?