Hi,
Another thing what I experienced, with more or less same issue, was connected to display settings and the media FPS.
In my case the Live TV have 50Hz FPS, and when the display (TV - HDMI) was set to 1920×1080@60Hz, got sometimes audio-video async issues.
That was some time ago, and after that I always used the Display/TV (Settings --> System --> Display --> Resolution) at 1920×1080@50Hz.
Try to change in the settings the display resolution, maybe you will find one without async issue.
Do you have set something in the Settings - System - Display - Whitelist?
Kodi and LE is an amazing combination, but sometimes need a bit of patience and sweat to have all working well and as we like it.