SOLVED: Codec issues on Sony Bravia using hardware acceleration

[TheDreadPirate]

Try unchecking low power encoding. That feature requires additional configuration in the OS that I'm pretty sure Synology makes difficult or impossible to perform. And it isn't required for your iGPU.

Also try passing in /dev/dri in its entirety instead of the specific renderD128 device or card0. The Intel driver will automatically select the first available Intel device in that path.