HTC Touch (CDMA) / XV6900

Every once in a while, I get this problem where the phone's ringer won't ring. Instead I hear nothing, or I hear the background from the other person's phone. It's quite irritating, as I only seem to get this once in a while. The problem is, the only fix I can find for it, is doing a hard reset. I really don't like doing hard resets. Does anyone know any other way around this?