RAX75 - No ipv6 connectivity

Picked up a RAX75 today from Costco, believe it's just a RAX80 without 1024 QAM on 2.4ghz.

Anyways, the router is handing out ipv6 addresses, but it doesn't appear to be giving me actual ipv6 connectivity over the web. I'm failing the ipv6 test sites as it just times out. The XR500 I have doesn't have this problem, and gives ipv6 connectivity over the web fine and I pass all ipv6 tests. I know the settings are the same, so I don't know what else I can try. The only thing I know is different on the RAX is that I saw this router supports LAG from a modem that supports it, which my SB8200 does so I have it enabled.