F5 LTM 11.5 : SYNC FAILED after applying iapps

I've had this issue since I upgraded to 11.5.1 HF2 och started using iApps. In my case nothing help, it does not matter if I've configured auto sync or manual sync. My own workaround is to restore a .ucs file on the standby node I created after clustering but before creating services. I restore it, restoring does not really work as it should neither so I need to manually reboot it. After that I perform a sync från active (with all the services) to standby (whitout any service). It works any time but it is pretty tedious.