We were delighted to receive this for my 3 year old's birthday earlier this month. A few days ago the sound suddenly stopped working. I've changed the batteries and tested the new batteries I put in, but the problem isn't with the batteries. I went to the Revain to see if I could exchange it but my only option was to return it and that was the last day of the return window. My son has a broken heart. It was his favorite present. Very disappointed.