Thanks for posting. I'm really sorry to hear that your Xbox NAT type is affecting you when playing online. Is your Xbox connected wired or wireless? You can try opening ports for Xbox live or putting your Xbox IP address into the DMZ in the hub's advanced settings which should hopefully give you an open NAT type. Let us know how you get on.
Thanks for getting back to me Good to hear that modem mode worked but yeah I can imagine people weren't to pleased if they were using the wifi at the time! Putting the Xbox into the DMZ shouldn't change the NAT to strict. I'd recommend rebooting the Xbox once you've done this and disabling the "instant on" option in the Xbox settings.