On long calls I've lost the voice from the other party. I can hear them but they can't hear me. But sometimes it is the opposite. I can't hear them but they can hear me. The calls start off fine but after a long time , the call gets half dropped. The other guy is not on sprint and this doesn't happen when he calls other people. This doesn't seem to happen when I call other people but I haven't had conversations that long with somebody else lately. This just started happening . It was fine before. Anybody else experience this?