Yeah, I tried all of the above. New CF card, reformatted and loaded the vol1 back onto it, etc.
I ended up returning it to the person I bought it from. I suppose, It's not beyond the realm of possibilities that it's my TI that's the issue. Not the NanoPEB.
As I only have one working TI99/4A, I did not have anything to test against. When I get my spare unit working then maybe I'll purchase another NanoPEB. Until then I have plenty of other projects to keep me busy.