What the heck has he done? I handed my new laptop over to a computer guy to get it running my old games properly for me. I've got it back now and the laptop sound is not working! Nothing, zilch, silence! What on earth can he have done to it? It'd be too embarrassing to ask him after he failed to get it gaming for me. Please computer experts of mumsnet, what might he have done and how can I rectify it?