Restarting loses internet connection

I doubt it's your upstream bandwidth. If your NAT is reading as Open but you can't connect to certain people or have connectivity issues, call Xbox Support and ask for Connectivity Department to get the right people. The NATs of BOTH players have to be messed
up to keep them from connecting to each other. Your NAT may not be truly Open. I had the same issues. What happens is many modems, Motorola included, exert a weak NAT of their own, a weak router function. The NATs of the modem and routers will overlap and
cause your issues. Also, a router may also need to be slightly altered to enhance online gaming connection. Both issues can be solved relatively quickly by Connectivity Support.

What version of the Xbox do you have? Is it possible you are connecting wirelessly and wired at the same time? This would create a network loop.

Additionally, it almost seems like an IP conflict. You don't have an IP hard coded on your Xbox that might fall into your new routers DHCP range, do you?

Hey hey, that's good news. You are most welcome, although I don't think anything I said was all that helpful, glad you were able to get yourself fixed up.

Ok i think i fixed the problem, i actually did a hard reset on the router and after that all the problems have been solved for some reason.

But non the less, thanx everyone for your answers

Have you tried connecting the console directly to your modem? It might be the router is causing the issue. Most ISPs provide really low quality routers.