@Clive_A Thenks for this advice. I tried changing to 2.1.15, keeping my existing configuration, but that didn't make any difference. However I then re-upgraded to 2.2.2 and tried a factory reset and...

I recently upgraded to the new 2.2.2 firmware, after previously being on the beta version. Since updating I've noticed that no incoming ipv6 connections are getting through, everything is timing out...