Plank refresh or crash after boot

Hi, since a few days plank started to refresh (or crash) a few seconds after boot. The issue appear at every start, cold boot, restart or login. I'm using the Phanteon layout, after boot I see immediately the dock (plank) without problems but after 5/6 seconds the dock disappears, so I have empty deskop for 5/10 seconds, and then it comes back and stay there until next reboot.
It's not a critical issue but I would like to fix this.
What can I try to do?