Hololens 1 streams audio only, no video

Hi,

Running virgin app in 4.23 preview (as it crashes in 4.22.3). Running HoloLens 1 with latest build (10.0.17763.678) and desktop on build 1903. When I enter the IP and click connect, the audio starts to stream to the HoloLens, but no video at all even when running. I can disconnect (audio stops), and reconnect (audio starts), but no video. The streaming splash screen showing the device’s IP and the instructions disappear when I connect, so the device is definitely connected to my desktop, just not receiving/processing the feed.

Have been following the instructions at HoloLens Streaming Quick Start in Unreal Engine | Unreal Engine 5.1 Documentation.

Any advice?