Forget forwarding and all that. Put the XBOX into the DMZ for a test run. Be sure your wifi is turned off for the test run and the firmware in the router is the latest.
I've got a question for any networking pro that might be able to diagnose what's wrong with my internet connection and cure my frustration! I've been through customer service with my cable provider and Microsoft, but continue to have issues with Xbox Live.
I moved into a new place a couple months ago and reluctantly subscribed for Comcast internet/cable. No real issues when browsing the web, downloading or uploading. The only real issues I have are when I'm playing on my Xbox. I have a wireless router, a Linksys E20000, plugged directly into the modem and the Xbox plugged directly into the router. Here are speed test results:
Download - 24.49 Mbps
Upload - 4.18 Mbps
When logging into Xbox Live, I connect quickly. When playing games (NHL or more recently Halo 4), I am able to find matches quickly and party up with friends with ease. In- game, movement is fluid and lag-free. Controls are responsive, graphics smooth. Then out of nowhere, I'll be dropped out of the match. In games like NHL, I am dropped from the game, but not disconnected from Xbox Live. In Halo, I will either get dropped out or will get a temporarily timed out before returning to the match as if it had never happened.
I can't seem to find any posts or similar issues on the web, but have talked to friends who have had similar problems. The best I've heard it described as is a "microdrop". It's as if it just drops out so quickly that it can drop me out of matches, but I could be simultaneously Googling away with no problems.
I've had port forwarding configured, opened my NAT type, etc. This isn't an Xbox Live issue, I'm sure. I've had it at several homes before this one and never have experienced anything like it. I suppose the blame would either fall on the router or Comcast's internet. Comcast says the internet connection is healthy and they are not very interested in troubleshooting.
Someone, please help!