Refresh rate switching

[postpapa]

What does this option do? Because it doesn't matter if it's set to disabled, scale on TV or scale on device the refresh rate doesn't switch.

In my little mind this should work like "set fixed refresh rate (whatever that might be) or depending on the media file.

If I use the external player on my zidoo z9x pro (and have it set to automatic switch the refresh rate) it changes according to the media file.
On the default player it does nothing. The result is that on certain media files you notice little or very noticeable stutter.

I hope someone can explain it for me :)