Phone won't answer or no audio on connect?

[yachtspecco]

I use the phone for work but it doesn't seem to be related to the number of calls. Frequently I won't have but 2 or 3 calls during the day and it still occurs. I have set the task manager to close on "X" because I thought it might be running out of memory but no change. Very frustrating when it occurs on an outbound call because it disables the phone for several minutes to reset and whomever I attempted to call will sometimes try to call back during the process.
First and foremost the things needs to be a reliable phone!!!!!!!
John