Hey it sounds like you have the exact same device I have.
Could you let me know how much success you have and if you can stop/fastforward/rewind a playing video without a system lockup?
EDIT: After reading some obscure posts here and there, I found the lockups seem to ONLY occur when the refresh rate is set to 60Hz
One of my TVs allows for 50Hz and that one works if I use that. But the other only has 60Hz and 24Hz. Using 24Hz is supper jumpy in the menus and durring playback. So I really cannot use the 50Hz solution. Either someone needs to fix 60Hz or I need to stay at LE 8.2.3 or I need to just abandon my Tronsmart MXIII-Plus boxes and get new ones. If I go the new box route, it is highly likely that I will not need LE at all.
The only use case I see going forward for LE is to get KODI working on hardware that generally does not run KODI well in the first place. I am fairly certain that newer boxes will have better implementation of MediaCodec and thus will not need LE.
When it comes to music I use to use open software called RockBox. That project is pretty much dead because who uses MP3 players anymore? I think LE could eventually head down the same path.
did you try the "refresh rate on " and a "white-list"?
you need to run your device without these settings only with a really old TV.
the "50hz" solution is only for old TV not supporting "refresh rate on" and a "whitelist"