ffmpeg exited with code 171

[harsha narla]

I have this hardware:
CPU: Intel Intel i5-10500T (12) @ 3.800GHz
GPU: Intel CometLake-S GT2 [UHD Graphics 630]
Ram: 8GB
followed official linux setup guide on my server  for harware acceleration (linux setup)

When i turn on transcoding and set to QSV / VA API, the playback stops (those that require transcoding) , I get

Playback error
playback failed due to fatal error

when digged through logs found out this line
[ERR]FFmpeg exited with code 171

files that doesn't require transcoding or when transcoding is set to off (which makes cpu transcoding) it is working fine but loads system a lot,

I want to use hardware transcoding . get struct at this ffmpeg error