When I answer a incoming call people can't hear me, but I can hear them perfect. It happens about 1 out of 3 calls, sometimes every other call. I usually end up having to hang up and call them and that works, but with in seconds of them answering I hear a long beep like someone holding down a number key. They can't hear it on their side, it's just my side, after about 3 seconds the beep goes away and everything's okay for rest of the call. Any ideas what's going on, it's really frustrating not just being able to answer the phone normally.