Had the same problem with my razor and finally got tired of it so got a new one. The Razor's are such a sensitive phone that the slightest amount of dust in the mike or headset will affect it. You can try using an electronics cleaner and cleaning the set. If it is clean then it might be acting up due to shocks like dropping it or sitting on it. Without opening the phone these are just guesses. But if the cleaning doesn't work bring it to your provider and it might be warrantied or if you have insurance it may be covered. Hope this helps.