CDJ 900 nexus sync

Hi,

Im using LINK to play via CDJs (latest firmware 1.31), linked to rekordbox via LAN switch.
I have an issue with SYNC, some tracks doesn't keep the loop synced to the other track, it runs away and destroy fading. Tracks are fully analyzed in rekordbox.
Is there any update planned to CDJs 900 Nexus?
Can anyone help me?
Thx