Hardware Transcoding not working on ubuntu server 18.04

Plex Media Server Desktops & Laptops
2

You are gonna need @ChuckPa to reply.
Do you have a dummy plug, when I run vainfo… I don’t get the x server error. I have a dummy plug in the HDMI port of my headless server.

vainfo
libva info: VA-API version 1.1.0
libva info: va_getDriverName() returns 0
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edit: pretty sure a dummy plug is necessary: