Wireless router causing connection problems?

[bigcatface]

OK, so introduction to the problem:
I've just moved into a building of about 5 apartments which all share the same (wired) internet connection. Main router is on the bottom floor and delivers internet connections to the different apartments via cables.
Since there are two of us in our apartment (me and the girlfriend) I thought it would make sense to connect a wireless router to our socket so that we can both access the internet at the same time without trailing cables everywhere.
Now, one neighbour claims that her connection has taken a nose-dive since we installed this (she knows it exists since she can see the signal) and claims that sticking a wireless router in tandem with the wired one is the cause of her woe. I've checked Google using about as many keywords as I can think of concerning this and I haven't come up with anything.
So, question is: Is there any truth to her claims? and if so, how can i work around this? Or is this the modern day equivalent of the crops failing because the 'stranger' came to town?

I would really appreciate any advice!

Bigcatface

 

[bill001g]

In this case turn off the SSID broadcast. She will no longer be able to see it unless she is a airmon-ng expert.

It could be your fault if you are are downloading lots of stuff but it makes no difference if you did it via wireless or wired.