Overlay mixer rendering mode?

[kimiraikkonen]

Hello guys,
By default Bsplayer runs at "internal renderer overlay" but if i change rendering mode to "overlay mixer" some of my videos cannot be opened with errors or some of them may go out of sync.

But if i use internal renderer mode, the problems do not seem.

What is "overlay mixer" and who can use it? What's the purpose?

My CPU is fast enough and my VGA card compatible with my videos (tested)?

Thanks.