Hi Michael,

I can share your frustration as it took me a long, long time to make it work through trial and error settings on the Codec Tweak Tool.

I think you need to open it and patiently go through each setting one at a time and change it then try to play it on the karaoki and undo if fail and repeat until something magically clicks.

I think the ones you need to change will be the ones associated with MP4s.

I can’t believe after all these years this problem is still going.

Give it a try and good luck.