2 Xbox Live Connection Issues

My family is trying to run two Xbox Live accounts on two different systems, one for my little brother's gaming and the other for Netflix/random times I feel like playing it. Recently, we cannot have more than 1 Xbox360 on Live at a time, if you try to connect with the 2nd system it will boot the first off of Live. A few months ago thou it worked fine, we were able to play at the same time, different games or together, without problems.

I cannot figure out what could have possibly changed or what is wrong now, so I'm hoping someone might know how to help. They are both connected wirelessly to a Linksys router, WRT54G. So, hopefully someone can help me figure this out. I'd greatly appreciate it.

I have the same router. Do you have manual settings for each xbox to connect to the internet on the console itself? (IP, DNS Servers, etc.) That is what you want. If you use automatic your router will automatically assign IPs to both xbox's (via DCHP), and if tries to assign an ip that xbox A is using to connect to xbox B, then A will disconnect. Use manual settings for both, and make sure all the necessary ports are forwarded for XBL itself. Use portforward.com if you want a step by step guide (just select your router model and "Xbox 360 Live").lKoRuPT

No problem, one thing I forgot to mention is to check your DCHP range. It will be on the main page when you log in, by default its usually 192.168.1.100 to 192.168.1.150 I believe. Then, when you pick your IP for each Xbox, make sure it is out of that range. For example I have one xbox and I use 192.168.1.240 (in the format 192.168.1.XXX). You should be able to choose numbers up until 255. You can also decrease the DCHP range. I know I'll never have 50 devices connected on my network at the same time. Glad it works for you. :)