I'll setup the syslog tomorrow, so hopefully I will know what is causing this the day after.
In answer to the Internet connection & power questions, it is plugged into a UPS so there shouldn't be any power problems, and I don't believe the Internet drops at all, would have to leave a computer on monitoring it to find out. The Internet does work in the morning, but a couple of times that the obi110 has crashed, I've not been able to get on the Internet, I get a feeling the obi110 has been almost denial of servicing my router, as when I turn the obi110 off everything has started working again.