For others that link above also fixed it for me. I have an Intel NUC11PHKi7C that has an Intel Core i7-1165G7 with Intel Iris Xe Graphics as well as an Nvidia GeForce RTX2060. When I plug a monitor into the thunderbolt port and set that as my primary monitor I started to get this error in plex.
Mar 17, 2022 20:25:17.019 [6280] ERROR - [Transcoder] [h264_qsv @ 0252e680] Error initializing an internal MFX session: unsupported (-3)
Mar 17, 2022 20:25:17.019 [6280] ERROR - [Transcoder] Error initializing output stream 0:0 – Error while opening encoder for output stream #0:0 - maybe incorrect parameters such as bit_rate, rate, width or height
Following the steps in that link transcoding works again. However it still reports using the RTX2060 but shows activity on both devices. I am not sure why thats happening, but hardware transcoding is working (or double working?). There is no other activity on the machine and when I stop playback both GPU’s go. back to 0%.
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