So more digging...
The cameras are outputting the following..
Bit Rate: 1536
Max frame: 25
IFrame Gap: 1 Unit:Second
Even after setting Orchid to match, it keeps changing the bit rate setting to 1843. What I have noticed since removing and re-adding the cameras from scratch it that I can only no play live in slow mode.
Does that help? Also tried the same setup with iSpy and BlueIris and they work fine.
I have Orchid for a good year or more now, not sure whats changed, but starting to feel like it might have been an update do it.