Xbox 360 Live Issues

Hey everybody,

I have been having problems with my xbox live. I'll first explain the smaller of the two issues I have encountered. Whenever I turn on my xbox it will not connect me to live until I test the connection, then it works fine. Not a big problem but I am curious about how to fix it cause it gets annoying.

The main reason I'm posting is because I can't seem to join my friends game. About three nights ago me and my friend finally got our connections working and could play resident evil 5 together. But now I am unable to join his game when he invites me. The settings haven't changed the only difference has been that the xbox and my laptop were off for a couple days. Any help would be appreciated since I've been searching the net and even tried calling xbox live support(which is a joke btw).

My router is a dlink DIR-655 and I am using a Network bridge from my laptop to my xbox to save the $100 it costs to buy the xbox wireless adapter.

I get no errors about NAT and I have even forwarded ports to my xbox(thats what got it to work the one night). Please help me!

Thanks for reading and even more thankful for help,
-Sotesko

Edit: Few more details that might help, not sure..
I do not have DMZ enabled on my router
Xbox has a manual IP assigned, rest is automatic
I've tried with and without a network switch
Tried with factory defaults
I appear to beable to join other games, but it hasn't been confirmed.

The router is almost as far across the house as it possibly could be sadly. But we figured that there must be a problem with the invite system for RE5. We can make a game and then manually join each other if we set it so anybody can join, but when its set to invite only and we try to invite each other it does not work. So I think it may just be an issue with the in game invite.

Thanks for your response! Still have the issue of having to test my connection every time I launch my xbox, but I can live with that.