Airport Mode Reset Needed

Hi folks.

Recently I've been having some issues with my iPhone 4. When I leave home, or change from WiFi network to another network, or just to 3G, I have to reset the networks by switching into Airport Mode, to tweak the wireless modems.

Is there something I can do to make this thing work properly? I've done a couple hard resets but it doesn't seem to want to fix anything.

Any advice appreciated. I haven't been able to find anything regarding this in the forums here.

Cheers