Hi. Experienced shooter, new to the C500. Got a couple things going goofy. Help please:

Multiple versions of same clip on CF card. Not that important right now.

"Proper" exposures IE 70-ish% IRE on caucasian faces result in quite bright images.
NOT clipped, but NOT actually overexposed, just overexposed looking. Ditto

And the killer is very important:

Apparent exposure fluctuations associated with subject movement in the frame.
The interviewee raises his hands, waves them around, and bam, the image dims.

Like a very fast auto iris or auto ISO kicking in.

Spoke to Canon Cinema support. They're having to research.

Thank you!