5th generation AEBS not working on 2.4, but 5 network works great.

Question

So...for 3 months, I had a very successfully connected AEBS.  I had a working and viable 2.4 GHz network running 2 iphone 4s and 2 wireless printers.  The working and viable 5 GHz network was successfully running 5 computers, 2 ipad2s and any other guest computer that would happen to stop by. 
Then..one day (3 days ago), the 2.4 GHz network just stopped connecting.  The printers wouldn't work and the iphones would say that it was connected, but still operatine on 3G..then just lose the network completely and say that it was 'unable to join the xxxx Network'. 
I paid $49 for apple phone support that basically had me completely reset the settings back to factory default and reconfigure..and it worked...for maybe an hour.  Then the phones dropped connection, the wireless printers never worked.  And on and on. 
My genius appointment was today and the apple genius gave me a brand new AEBS..I saw him open the box..it wasn't repair stock..he took it off the shelf.  He claimed the 2.4 GHz antenna was bad and a new one would solve the problem. 
I reset eveything up today....same problems. 
the 5Ghz network is running fine...brilliantly.  All ipads and computers work like a charm. 
I am connected through a Uverse 2 wire box..but as I said, I had a perfectly working system for about 3 months. 
Just for kicks and grins, I rebooted the 2 wire box..stil no luck. 
I am hoping that someone here in this vast universe of knowledge has an idea of what may be wrong...it's driving us crazy. 
Thanks in advance. 

Answer 1

Chances are....about 3 days ago....someone near you added a new Wi-Fi setup at their house, a wireless camera/security system, or even a new cordless phone setup.
One of these devices, or another electronics device like a satellite receiver, television, etc., is interfering with the the 2.4 GHz band on your network. Unfortunately, this is a common problem with the 2.4 GHz band due to severe overcrowding of wireless networks.
For example, a few years ago, my wireless network, which was 2.4 GHz only at the time, started suffering from intermittent sudden slowdowns and complete disconnections. I tried, but could not locate a source of the interference...even changed the cordless phones to other models that did not operate on 2.4 GHz, as most cordless phones do. Changed channels, tried a different router...same problem.
One day as I was working at my desk, I noticed my neighbor....across the street....coming out of his house talking on his cordless phone, when my network speed suddenly dropped to a crawl. By the time he got to the street to his mailbox, my network crashed.
Fortunately, my neighbor is a good friend and he usually remembers to keep his cordless phone inside. When he forgets, I know exactly where he is and what he is doing....without having to even look out the window.
For more information about wireless interference, you might want to read the Apple Support document on the subject:
http://support.apple.com/kb/HT1365?viewlocale=en_US