Mercury Transmit performance M2 Ultra

My M1 Ultra (on macOS 12) died, I'm now on a M2 Ultra (on macOS 13 Ventura), but for some reason I don't get the same performance using the Mercury Transmit to a HDMI connected UHD TV when working in ACES. Even when the HDMI monitor is set to HD it isn't able to play a 4k comp at full framerate (25fps). An HD comp seems to work, or lowering the resolution to quarter (downsample), but higher that that it stutters. This wasn't the case on my M1 Ultra, I could playback 4k shots at full framerate. Not sure why that is not the case anymore, but a couple of this changed basically at the same time; could be the M2 Ultra, could be macOS 13, could be AE 24, maybe something changed when using ACES? 

FYI, when using DaVinci Resolve, I get full speed, full resolution playback on that screen, so it isn't the tv or the HDMI cable, or the ability to push UHD data from the computer to the TV. I haven't tried Premiere (not installed on this new computer), but I would assume it would work just fine.

Any ideas anyone? Or are my expectations just to high and is the Mercury transmit engine just not up to the task when using ACES/float at over HD resolutions. I mean, I also couldn't find where to set the Display Color Space for the Mercury Transmit display, so maybe ACES in combination with Mercury Transmit is actually just not supported?

Or am I missing something here?