How to disable intermittent notification sound that is not a notification.

Since I got my Epic4g I've noticed it intermittently makes a notification sound that none of the sound files on my phone sound like. When I turn on the screen there are no new notifications and no clue as to why it happened.

I thought it might be when the battery is fully charged but then noticed it does it when unplugged from the charger.

Today I discovered that it is the same sound that the phone makes when you turn airplane mode off. So if you hold down power, turn airplane mode on and then do it again and turn airplane mode off it will make the sound as soon as the radio pops back up in the notification bar. Figuring it had something to do with the radio being enabled, I rebooted my phone.

Sure enough, when I reboot the phone and the radio status pops up in the notification bar the noise occurs.

This happens on my girlfriends Epic 4g as well, so I know getting it swapped won't fix the problem. I don't want to disable the radio at night in case I get an emergency call.

Anyone else having this feature? Anyone figure out how to disable it either through UI or deleting a sound file somewhere?

Thanks,
JC

i think it's the roaming or out of network notification.  do you have bad 3G service where you are?  i've read that people with bad or intermittent 3G services are getting the notification beep and can't turn it off.  they are quite angry about it (i would be too) because there's no way to turn it off.

My phone is on roaming at my desk at work, but I don't get the sound when I arrive at work in the morning.  Usually at least once during the day it will make the sound, however.  I called Sprint and they recommended a hard reset, but I heard the sound again at about 4:00am this morning.