COD4 - linksys router disconnects?

I purchased call of duty 4 [the mac version] to run on my early 2008 white model MacBook. {2.1 GHz Intel Core 2 Duo, 4GB RAM} the game runs *okay* with the highest graphics settings, (exluding anti-aliasing, and depth of feild-since those two go to crap on the mac version)

I have found two, pretty major problems with the game so far...

First, in single or multiplayer, the game runs great, until somebody besides me uses an automatic weapon, the ones where it shows the light of the bullets coming out, then it starts to freeze up, but after i kill them and they stop shooting, its back to normal.

Second, this is the one i care more about, I have a Linksys WRT160N wireless router which I play cod4 on from my bedroom. Idk if the problem is with my mac, cod4, or the router, but everytime i try to join a game in mutiplayer, it times out on the connection, then I quit cod4 and check my airport, which is down to 3 bars instead of the normal 4, also I have no LAN connection, and no WAN connection, yet I check the avaliable wireless spots and it is still there. When this happens every device connected to the router looses part of the signal and all bandwidth andywhere. Also you lose the ability to connect to it, i get an error, and this only happens with cod4.

From what I've seen on google, it looks like cod4 does this a lot with PS3 and Xbox but i don't see anything about pc version, say nothing of the mac version.

Has anyone had this problem? Am I missing something?

 

Thanks for the reply-

I can't test it now but I think you're right on the first one.

On the second I was hopeing for some small setting switch on either mac or router, I tryed to install DD-wrt on my old router linksys wrt54g, but bricked it in the upload, and I suppose I'm full of problems...
1. Ddwrt not made for wrt160n v2 I believe
2. I'm still working on getting my Ethernet to work right on my mac...
(need wired con. To upgrade firmware...)