I have an existing Airport Extreme BaseStation set-up as my wireless router. It is located on the far end of the house. My computers are close to the base station and can get goo wireless signal. Recently I bought an Airport Express and put it in my bedroom (other end of the house). I hooked up my powered speakers so I can stream iTunes. I set-up the Airport Express to act as Extend Wireless Mode. I was able to stream music from my iTunes on one of the computers to this Airport Express. My signal in my bedroom increases since I added this but I noticed that the signal on my computers close to the base station decreases significantly. I dont know why it is doing it? Is it because I set-up the Airport Express to act as extender? The signal around the express is good but the signal near the base station is bad.