UE5.1 6K Video Vulkan Performance Issues

Since 4.27 if you try and play a 6K video with Vulkan there is a big performance drop unusable. In 4.27 I managed to get our app to run with OpenGL but in 5.1 I haven’t managed to do that using OpenXR.

My understanding is to use Vulkan as much as possible but atm this is not possible.

What advice is there for 6K video playback on Vulkan in 5.1. or getting OpenGL to not crash in 5.1?