Hololens 2/Unreal Engine 4.27.1 / Video Issue

[UMLnow]

I'm trying to play a .mp4 file (h.264) via a widget blueprint, which works fine in the editor/via remote streaming. Deployed to the device the widgets stay black and nothing starts playing.
I also tried activating the Hololens Media Player Plugin but then I get an Error Message that reads: "Could not create Media Playback Engine Component."
If i enable the Hololens Media Player Plugin, will unreal use this Plugin automatically or is there any other action i have to do?

Does anybody can give me an advice what to do? Any help would be greatly appreciated.

Thanks in advance!

[fieldsJacksonG]

4.27.1 has a known issue with the HoloLens Media Player Plugin when using DX12, which the HoloLens will default to.

You will need to either update your project to 4.27.2, change your default RHI to DirectX 11, or apply this change to your local Unreal source:
https://github.com/EpicGames/UnrealEngine/pull/8477