Cannot get AirPort Express to Join Wireless-N Network

[freaky]

I just bought a new AirPort Express (802.11n / A1264) and would like to use it to play music on my iPod Hi-Fi as well as for BD-Live with my Blu-Ray Player or my Xbox 360. I have two routers -- an older Airport Extreme (cone shaped - for my 802.11g network) and a newer model Airport Extreme for just my 802.11n network. I have an iMac and Macbook connected to the N network without any problems. For some reason, the Airport Express will only connect to the G network, but it just shows an amber light when I configure it for my N network with the following settings:

Join a wireless network (also tried Extend)
Allow Ethernet clients
WPA2 Personal

Can someone tell me what may be wrong? I cannot figure out why the Express will not ever join my Wireless N network no matter what I do!

I don't know what it is with my 802.11g network but it SUCKS! I live in a house (not apartment) and most things connected to it are within 25 feet. The router is in the basement and the devices are no more than 12 feet higher than it. The devices connected to it are my two Series 3 Tivos, Xbox 360, and AirPort Express. All three things have flaky connections to the network. Sometimes my TiVos don't show up on each other's screens, I get disconected from Xbox Live from time to time, and playing music on my iPod Hi-Fi is very choppy. Could the AirPort Extreme just be bad? My newer Extreme seems to work well, but that's also only running 802.11n.

Also, can I use a splitter or something and have two RJ-45 cables going out to my blu-ray player and Xbox so I don't have to manually switch the cable all the time?

 

[Satcomer]

OK before you turn on the Airport Express you to first launch /Applications/Utilities/Airport Utility and get into your Airport Extreme.

Once in Airport Utility do a "Manual" setup and find out what your Airport Extreme is doing for a wireless setup. What security, frequency (b, g or n or a combination). Then also in the Airport Extreme "Wireless" tab make sure you make note of the "channel" it is broadcasting at (so you can match on the Airport Express (See the Note)). Also make sure in the airport Extreme you check mark "Allow this network to be Extended".

Then while the Airport Utility is STILL OPENED turn on the Airport Express and then use Airport Utility to match it up to "Join" the Airport's Extended network, match all the Airport' settings to join to it.

Note download the free program iStumbler to see all the channels your neighbors are using to make your channel setup different to reduce a case of possible jamming.