Kodi 17 – rc3/rc4: problem in slideshow: playback of videos is stumbling

Now playback of videos in picture slideshows has a new bug.
The Video is played and returns nicely to the next picture when it is finished BUT:

The playback of the video is interrupted each second for half a second – so it stumbles all along…
I found out by chance that when you move the mouse while the video is playing the video plays nicely and smooth.

The problem is not with the videos. Because when I play the video OUTSIDE of slideshow it plays nicely – and of course in other players like vlc.

Please help
With kind regards
Martin Klein