I've got a weird problem. Every so often my rooter (a Thomson TG585 v8 running version 8.2.7.8 of it's firmware) reboots itself.

It seems to be associated with this message in the event log:

FIREWALL replay check (1 of 2): Protocol: ICMP Src ip: 183.178.144.177 Dst ip: xxx.xxx.xxx.xxx Type: Destination Unreachable Code: Host Unreacheable

xxx.xxx.xxx.xxx is my external IP address

183.178.144.177 resolves to 183178144177.ctinets.com

We've got a student from Hong Kong staying with us at the moment and the reboots seem coincidental with him starting up his laptop. I say this because a check on ctinets.com shows it to be based in Hong Kong, though our guest's laptop doesn't appear to have any software related to this company installed. I say "apparently" as he is running the Chinese version of Windows and his English doesn't cover technical subjects like this.

I know this is an incoming message but I was assuming that it was in response to something on the student's laptop which is why the first thought was malware, but we've got anti virus on all the other machines and have run malwarebytes on his with a negative result so I don't think the problem is due to a virus or (known) trojan.

What else can I do to stop this and identify the cause?