RB1100AHx2 Ipsec causing 100% CPU core usage

Hi All

I’ve looked around on the forum and not found anything quite like I’m experiencing, so here goes

I have a RB1100AHx2 at head office, with 3 sites connecting via a IPsec VPNs
Everything works fine for a while, and then all of a sudden everything stops working.
If I try have a look via winbox at the IPsec policies on the main RB, it shows there is nothing, which is not try, the policies exist and if i try print the policies the command just hangs.
Upon further investigation, ipsec used 49% of the total CPU(100% of one core), and all the IPsec tunnels are dead. The only solution thus far is to reboot the router and all is then well for a while and the cycle repeats itself.

Head office is off a static IP on a fibre line, the 3 branches are on dynamic IPs, 2 off a DSL line and 1 off a fibre line
I have scripts to update the IP addresses on the various policies etc

I am lost as to where or what the problem could be. I have a second company with a similar setup and that works fine, although the RBs are different models.
Could there be a bug with the RB1100AHx2 and IPsec?

Any suggestions please

It could be, generate supout file and send it to support.

Is there anyway to kill the ipsec process that is currently using the CPU?