waveform moving constantly with several tracks with synchro or not

since version 4.4 of rekordbox dj,waveform of lot of title are moving constantly on mix.even of version 5 beta.
see the picture with version 4.3.1,see the beatgrid.

see the beatgrid with rekordbox 5 beta and the same problem vith version 4.4 and 4.5

here a video of the problem.https://www.youtube.com/watch?v=UKGO6BorCn0 

thanks you!