I had all the same issues as everyone else.
THEN I purchased a “Patriot” 32GB USB flash on amazon after researching what some of the faster read write speed devices were. That one had good reviews for speed.
I plugged it in right out of the box (created the TeslaCam folder) and is has not so much as hiccuped once in 2 weeks of driving.
Can’t really say what the problem is or was.
But I do know a USB that worked for me.