iPhone 5 WiFi is deadly slow

Hi,

 

I have an iPhone 5 (iOS 6.1.2) and a new iPad (third generation), and both devices are connected to my WiFi network. My AirPort Express runs firmware 7.6.3 and its wireless security is set to WPA2 Personal with radio mode 802.11n (b/g compatible).

 

I cannot precise when I first notice the problem. Not sure if was before the AirPort Express update or some iOS firmware update. The problem is that my iPhone 5 WiFi is deadly slow. It's virtually impossible to download an app from the AppStore or sync Rdio songs. My iPad's WiFi (and my wife's) is working as expected, though.

 

Things I've tried so far:

 

- I've changed my AirPort Express security to WEP

- I've changed my AirPort Express to 802.11n

- I've changed my AirPort Express to 802.11n 5GHz

- I've reseted the Network Settings

- I've tried to download apps using other 802.11n connection (at my parent's)

- I've tried to download apps using a "unsecure" network

- I've restored my iPhone 5 to 6.1.2 using iTunes (setting it as a new iPhone)

 

I have no idea what to do next...

 

EDIT:

 

- I also did some tests with the Airplane mode ON, just to make sure the iPhone was connected to and using the wifi connection to download the apps and sync Rdio songs.

View the original article here