I am having an issue with 9.2.1 on the RPi4 (I know it is still in development). On each video file (regardless of MKV ot M2TS or 1080p or 4K) the video stutters and at the same time, the audio starts playing ahead of the video. The effect gets more pronounced until the audio is a good few seconds ahead and it becomes unwatchable. If the video is paused and resumed, this is corrected for a few minutes or so before it starts again.
I have tried combinations of turning on and off MMAL acceleration, switching "adjust display refresh rate" (on start/stop , always, off), "sync playback to display", as well as adding a vast range of resolutions and refresh rates to the whitelist. I have also turned on hdmi_enable_4k=1 in config.txt but this seems to have mde no difference.
I am new to the forum and reasonably new to LibreELEC so apologies if I have overlooked something simple or if this is a known issue, or indeed if I am just being dumb. Any help would be appreciated as this is frustrating, as you can imagine! If logs would help, I would be happy to supply.
The issue appears to be similar to that described in the thread 2 RPI 4 model B, playback issue on 1 although that issue presents with just one file.
Many thanks in advance,