Audiovox SMT 5600 / SPV C500 (HTC Typhoon)

Does anyone else have this problem? When I plug the included headset into the phone the microphone on the phone itself doesnt turn off. So, when you put the phone ina pocket and talk on the headset, people can hear the noise of the fabric rustling on the phones' microphone!! Is there a setting I am missing?


Thanks, Mike