The Sony a9 full frame mirrorless camera ($4,498) just started shipping a few days ago and we already have the first overheating reports (Sony had several overheating issues with different cameras over the years):
"After 20 minutes of shooting That 1 Cameraguy experienced an overheating indicator in 80-degree weather after 20 minutes of shooting.: (SonyAddict)
Here is the related video:
A similar report came also from dpreview:
But one unnerving thing was that the high temp warning came on. I was admittedly in the sun most of the time but it's only around 65 degrees today in NJ. I did have the camera on and shooting probably for 40-45 minutes nonstop. (No video, by the way.) I set the sleep timer to 10 seconds and that seemed to help. But this worries me a bit for summer/warm weather shooting.
Few other issues reported by Sony a9 owners: