I had my GoPro 7 Black record about 3 hours of video while at Hubbard Glacier in Alaska on May 25th. I did this by mounting the GP to the rail, connecting a 72Wh Lithium battery and powering it up and pressing the shutter button. I verified that the GP was indeed recording at Linear 1920x1080/60fps MPEG-4. After returning and removing the 64Gig memory card, I inserted into a WD portable HDD to back up the files. It appeared that 12 files were created of close to 4G each (except for one being 1.3G) that were about 17 minutes long.
After getting home, I was only able to play the first file that completed recording ~2:38pm. All of the remaining files play only the audio track with a still image showing on the screen during playback. When I have CyberLink PowerDirector 17 produce and combine the 12 files, I get a 3 hr video that freezes on that same still at about 35 minutes.
As an experiment, I took the files directly from the memory card. The freeze up happens at the mid point of the 2nd file. So did the camera just decide half way through writing the 2nd file to simply record the same video frame on every following frame for the continuation of the filming? If it did, then there is a flaw in the camera. All of the other single videos on the same card are fine. I put the ending file at Dropbox if anyone wants to look at it. It is somehow corrupted. The one thing odd about it is the time stamp. It shows 4:41pm but is the last file in the 3 hr video which did not end until 5:41 and is numbered correctly by the GP. Link to the damaged ending file is at https://www.dropbox.com/s/ca4eqexrq5...23634.MP4?dl=0
It shows the same issues when opened by multiple people, different computer, and a host of different player/editors. So I'm guessing that the camera ruined my filming of our Hubbard Glacier pass. Thank goodness I was up on deck using a Nikon D7500.
As another test, I put the card back into the GP. When pulling up the contents, it only shows the first file which it plays okay.