A BusinessWeek article purports that Apple is currently testing a fix for widespread loss-of-signal, poor signal and fluctuating signal issues with the iPhone 3G.
Peter Burrows writes:
"Apple and Infineon are currently testing the fix, which will be included in a broader update of the iPhone's software. iPhone owners will be prompted to install the update when they synch their iPhones to a PC, just as they have on many other occasions. In its statement, AT&T said, 'We urge our customers to synch iPhone 3G to iTunes frequently to ensure they have the latest software updates.'"
Users, in droves, have reported signal strength/reception issues with the iPhone 3G when utilizing the 3G network in areas with purportedly strong coverage, per AT&T and other carriers? maps. Most disconcertingly, phones from other manufacturers often deliver excellent 3G signal strength on the same network and in the same location as signal-crippled iPhone 3Gs.
Several users have exchanged their iPhones for replacement units with no improvement.
The iPhone 3G automatically switches between 3G and 2G networks for voice and data connections. In theory, the phone should hop off 3G when signal strength is too low or non-existent, and hop back on when the signal gets better. In our experience, however, the iPhone 3G isn?t aggressive enough regarding the switch from 3G to 2G. In other words, you may find that your phone stays connected to a 3G network when the signal strength is too low to allow incoming or outgoing calls.
The simple solution is to manually turn 3G connectivity, forcing a switch to 2G ? which may take several seconds ? and likely a boost in signal strength.