In the last week my graphics card suddenly started losing audio/video sync when playing back video at 3840x2160. After talking to support for the software I was using, I changed the resolution to 1920x1080 and it plays fine. Rolled back the video drivers a month to see if I could pin down the reason for the sudden change, but still no change. Anyone any idea where I might look to find the culprit?
Thanks for the pointer Doc. However, After trying LOTS of different things I have found the culprit and the culprit was ME. In a effort to improve things i made changes in the BIOS. Things got worse and so I set the BIOS to factory defaults. Stuff that had stopped working worked again. However, the factory default for CPU power level is 6 Watts, far too low. I set it to AUTO and everythings working again at 3840x2160. 🙂