IPsec site to site to checkpoint UTM drops every few minutes

[Jeeper]

Hi all,

I have a problem connecting IPsec VPN site to site to about 12 checkpoint UTM Edge-1 devices. The connection drops every few minutes and after a few minutes it comes up again. It's not a steady cycle but looks like a random disconnection that happens on all those devices.
From the status -> IPsec i can see that the tunnel does not really disconnects but rather looses phase 2 (at least it seems like it).

This is a new pfSense 2.3.2 installation that is replacing a Checkpoint appliance 2200.
It is also connected to 7 sites with Cisco RV130, one site with Checkpoint appliance 730 and one more pfSense 2.3.2 (Via Openvpn) with NO issues!

I have tried adding the internal and external IP's of the UTM device to the IPsec configuration, play with DPD settings, change authentication configuration, key & encryption configuration with no luck.

Do you have any ideas as to the issue with the CP UTM Edge-1 device? I realize that they are quite old (2012), but they are good, stable appliances that are suitable to our implementation. They all have the latest firmware.
Maybe you have a better or different configuration in mind that will make a more stable VPN to those devices?

Thanks!
Lior.

[Jeeper]

Anyone?
Ideas maybe?