Sorry Bill..
It sounds like your car, that's why I said it.
High gear is trying to apply while the 2nd gear band has not quite released yet. You will have to forgive me but I haven't had a T/F since 1992. P/G ever since. But mine was a Pro Trans best of the best back then. I think Dave Smith was who told me of this problem back even before I got a trans from him. (pre Pro-Trans)
I remember it felt like the trans was binding up trying to get to high gear. So if I remember right, they made the valve body delay the high gear full apply until the band had released completely.
Hey, I'm probably wrong, but I am just throwing out a possibility that I ran into back when I ran those things. It just sounded really familiar in your video.
And it sounded the same in each one.
My band was really burned up when this happened.
It started happening when I used a lot more power...N2O.
Mph was down too.
I hope you find it.
Call Dave Smith @ Pro Trans in Lancaster, CA.
(661) 940-7400
Chris..