Thanks very much for the reply and sorry I didn't respond sooner. The firmware was 'old' and has since been upgraded. This didn't completely resolve the issue, although we do have a little more stability we've experienced 2 outages since. Not getting a lot of luck with the IT support guys and their cronies out in the cloud, so I assume there's nothing obvious in any logs. I've asked if an additional controller can be installed, maybe I'm just asking too much of a single controller..?

Thanks again for the additional info.

Paul