WAP Loses Connections with Multiple Users

I have a problem with my home WAP. I have now gone through a Linksys and a Dlink WAP. The problem I have is that my wife can work fine all day long. When I come home and log in, I knock her off the wireless. When she renews, she knocks me off, and so on…. If I shut down, she is fine again for the rest of the evening. We have tried DHCP assigned addresses, where we DO have different addresses, we have tried statically reserved assigned addresses, with the same unwanted results.

Where do I check to find what is causing my issue?!?!?!