You wake up in the mid morning, very hungover from the night and day before. Power up mac and shock horror, no sound. The hifi works with the radio so the speakers work. You take the phono jack out and... Your internal speakers are silent. In a fury of 'fight or flight' speed you try iTunes, open up sound/system prefs and disk utility. In the few minutes that pass you consider your last upgrade, did you miss something? Was there a loose cable left? So do I have time today to get to store? How much for a new mini these days? Actually, wait a tic. What does Mroogle say? Reset your Pram Cheers MR. You have saved much bacon yet again.