Our new X with 2019.12.1.2 suddenly developed a problem with the DashCam / SentryCam USB storage. First, the icon for the DashCam disappeared. After resetting the car (power off, wait 90 sec, turn back on) the icon is back, but it always has an X on it. It's not saving SentryCam events either.
I've tried three USB sticks (one 64GB disk that we were using just fine until now, a 32GB one that's worked fine as the MP3 music source, and a new 512GB one), I've made sure they were cleanly unmounted... I've made sure they're FAT32.... I've reformatted them twice with Linux as FAT32... there's a TeslaCam folder, etc, etc.
The old 32GB one will show "USB" as a music source and show the songs on it, but it won't store SentryCam and the DashCam icon stays X'd out (yes, it has a TeslaCam folder). The new 512GB USB stick doesn't work or show music on the disk. The 64GB one shows music but doesn't work for clips.
We were using the 32GB in the driver's side front USB for music, and the 64GB stick as a dedicated DashCam/SentryCam on the passenger side front USB port. That's worked for about two weeks. For testing, I've tried only putting one drive in at a time as well, no change.
Every time I pull a drive with a "TeslaCam" folder I have to run it inside to repair the filesystem or it will be marked dirty... but there's nothing in the TeslaCam (No RecentClips or SavedClips folders, etc). Pulling a disk with only music and no "TeslaCam" folder seems to unmount cleanly for some reason. (?)
The SentryCam option in the menu allows me to turn it on and off, but it's not going to store anything to the USB.