3rd Party App 4k Video Issues on Z12 Ultra

Hi. My Z12 Ultra has video issues when trying to play 4k streams on my Bell FibeTV app, but they work perfectly on my Z Mini.

When I try playing any 4K stream on the Ultra, the audio is fine, but the video always plays at what looks to be twice the speed. Always!

I've gone through every possible regular and developer function I can find and tried toggling them all one at a time and a few at a time and nothing seems to work and it's making me crazy! I've tried manually fixing the display mode to various 4k formats, turned AFR on and off, etc...

On my Z Mini, it just works without even needing any dev settings changed.

Both units are on the latest firmware. There is no beta firmware available for the Z12 Ultra when I manually bring up the option.
I've matched the settings of the Mini to the Z12 as bast as possible, however I see the Mini shows Color Space Settings as 8bit vs 10 and 12bit on the Ultra which I feel shouldn't have any bearing on it.

The Ultra is NOT cheap and I expect much, much better, TBH.

I suspect it's a missing codec that the Mini had by default and the Ultra does not.

Anyone run into this issue and have a fix?

Thanks.

Thanks. Just an FYI: A competitor's knockoff device has it working flawlessly.
It's not really a deal-breaker, but it would be very nice to have.
I'm rooting for Formuler and am willing to be an alpha or beta tester, though!!

Thanks again!