Why will my laptop's sound not work?

My laptop [(Vaio Vista) VGN-CR220E] is having a few minor problems. First is my battery on full last 3 hours- that's what it says- really I have 2 minutes. And second [MOST ANNOYING] is my sound does not work. I have had this laptop for nearly 3 years, and the sound now likes to come and go (more going than coming) with crackles. I haven't changed my sound driver or card so rule that out. Also when im playing music down by the volume the green bar will bounce around like it's playing and all, but no sound. I think to plug in the headphones- never know- and they don't work either. What do I do?