[fritsch]

I'm having this same issue running 17.6 on my 9 year old Win 10 machine which has a newish GT 710 GPU.

I've found the following results on changing various settings playing a 1080p x264 video:

DXVA On, Refresh Rate Change On, Sync Display On - Continuous stuttering, CPU ~30%
DXVA On, Refresh Rate Change On, Sync Display Off - Frequent stuttering, CPU ~15% -> No stuttering with overlay
DXVA On, Refresh Rate Change Off, Sync Display On - No stuttering, CPU ~30% BUT some noticeable audio clipping with bitstreaming to AVR
DXVA Off, Refresh Rate Change On, Sync Display Off - No stuttering, CPU ~30%, audio fine

I've stuck with the final option (software decoding ) as it gives the best stability albeit with a higher CPU load.

It's a frustrating bug given the overlay "fixes" the issue. Has anyone worked out how activating the overlay can possibly be influencing things?

Just use v18 nightly ...