I haven't had any issues with mine when not mounted on quad it's used in the car I am using a class 10 micro card on mine
I am using a class 4 32gb card here. Problem seemed to happen when I swapped the 8gb card I had in there to the 32gb thats in it now.
Saying that it gets used every time car is started (it auto starts with the car) and the card issue has happened twice in a few months.
Could have been down to a bad conection on the card due to the cold weather or anything.
Im going to have a look for a better spec 32gb card as I thought it was higher spec than it is.
edit got myself a class 10 32gb card on the way now so hopefully that should solve the card issue.
Saying that it hasnt happened enough for it even bother me anyway as it lives in a pretty horrible place (direct sunlight and freezing cold never does electronics much good)