Dude - I got the exact same problem.
Just like you I upgrades from a Gen-4 to a Gen-5 for the boosted wifi signal, but I got the nasty side-effect of a crippled XBOX360-Slim wireless connection.
My Gen-4 unit was able to stream HD content seamlessly to my 360-slim but the Gen-5 cripples it down to a trickle.
I think there may be some compatibility issues between the wifi chip uses in the Gen-5 (which is a Broadcom) and the 360-Slims internal wifi card.
The Gen-4 used a different wifi-chip inside so apparently the pairing to my 360-slim was excellent.
I'm just waiting for either Microsoft or Apple to fix this through a firmware update, as I can see this becoming major issues with 360-slim and Gen-5 users...
I have no issues, but I am using
And the only device connecting to 5 GHz SSID (channel 149) is my Xbox 360 & apple TV
but I have a different issue, my SSID's will vanish for long period of time, no internet connection, light will be green, unless I unplug the **** thing and power it back up net connection won’t come back, I can unplu the ethernet cable and plug directly to one of the computers I am online, sometimes just for couple of seconds its invisible but it will come back, I use inSSIDer2.0 on my windows 7 PC running all the time so I can record when it goes off and comes back,
I am on different channel from everybody else (20 Wireless networks, 18 belkins and the SSID goes like insight_wifi_1234, and 17 of them on channel1 and one of it is on channel 6, another one is a Linksys channel 6, last one is a netgear on channel 9) in my neighborhood, and inSSIDer does not show any interferences! When my SSID's vanish. (2years back there was one network which was broadcasting on channel 11, thankfully it was open, so just signed in as admin on that and changed I to 6 ;-) then I was using an Airport Express)
All my devices are n capable, everything else connects to 2.4GHz SSID on channel 11
Thankfully I buy my apple products from Amazon, so returning them and getting another one is a no problem, -apple's 15day ctach not applicable 8-) - so I am on my second unit and this one too started showing the same behavior. Called apple care and the guy wanted me to trouble shoot by resetting it. I said thank you have a good day. I might try a 3rd unit and if that’s going to be same behavior I am going back to Linksys E4200 which has same hardware as APE.
Same exact setup with the same problem even after the 7.6 firmware update for the AAE that was recently pushed. It's definitely seems to be a compatibility issue vs a port forwarding or firewall issue. Everything works great except xbox 360 media extender to windows 7 pc through the aae 5th gen. If you found a solution please post.
Very similar problem here.
I just upgraded my main airport express from one of the older 802.11g types to the latest airport express 802.11n 2nd generation. I have an Xbox 360 slim with built in wireless connecting to the airport express and previously I was getting a 54Mbps wireless rate (G mode) but now I'm only getting 11Mbps (as measured by the airport utility) which gives an actual data throughput of maybe 5mbps at the most. (Hard to measure exactly on an xbox, but I can tell from stuttering on high bit rate streamed video that the speed is limited...)
The Xbox is only 3 metres from the airport express in the same room so its not a distance issue. I've done lots of research and apart from a few postings like this, no real solutions and very little information on what seems to be an incompatibility between the Xbox 360 slim internal wireless and the N mode of the airport express.
One article suggested to disable separate naming of the 5Ghz network, but this did not help for me, and I prefer to have a unique name for 5Ghz so I can set my 5Ghz devices like the iPad to always connect on 5Ghz.
If I disable N mode it will connect at 54Mbps as before but the whole point of the new airport express was to upgrade my network to N compatible, as well as dual band 2.4/5Ghz. All my other devices connect at N rates fine, and performance is excellent on all other devices.
This seems like an interoperability issues between the two devices - I've read that the external 2.4/5Ghz N adaptor for the Xbox 360 (which also works on the slim) does not have this issue, but I don't see why I should pay more for an external adaptor when it has built in wireless.
Unfortunately I don't think we're likely to ever get Apple or Microsoft to admit to the issue or do anything to fix it. In the mean time I've plugged the Xbox into a second airport express cofigured as a WDS client - I have one nearby connected to the stereo anyway for airplay streaming, so its just an additional ethernet cable but its a shame I have to do this...
Hi!! mmm..we have the same problem, man!
when I use the N wifi i get a 5mbps connection with my xbox 360 & airport extreme 5th generation....with G wifi it's all ok, but i bought the airport extreme for use the new type of wifi :/