Sound Stops randomly

[Mandy Brown1]

My new samsung galaxy ace 3 keeps randomly loses its sound, it will vibrate but no sound on any level. I do a restart on phone 3-4 times and no return sound, I have to turn off the phone instead of restart and then after few seconds turn it on before sound returns. This is happening 1-2 times a week and I only have the phone since end of April. Any ideas what can I do to stop this happening again or is it a faulty phone that needs to be returned to shop as it is still under warranty?