Dean, thanks for replying. The temperature in the arena was definitely above freezing where I was taking pictures. I have never experienced anything like this with the 7D or 5DIII. Here is what was said in the repair summary:
"Your product has been examined and it was found that the product performed according to specifications we were unable to duplicate your concern.Although, we do suggest to shooting in high speed continuous or low speed continuous instead of high speed continuous+ because high speedcontinuous+ will allow you to take images very very quickly so quick that even when taking your finger off the shutter button the camera will still takesome unwanted pictures because it's shooting so fast. The high speed continuous or low speed continuous will still allow you to take serval picturesat a time but it won't be as quick as the high speed continuous+ when shooting. Product functions were confirmed and unit was cleaned and checked,thank you for choosing Canon."
I just wonder if anyone else has experienced this with any of their canon cameras?