My laptop has stopped playing sound?

MY APPLE MAC POWERBOOK G4 LAPTOP STOPPED PLAYING ANY SOUND AND WONT PLAY A SONG IN ITUNES?????***HELP***?

• i have a ppowerbookg4 laptop;; its been having too many problems lately;; i did nothing diffrent for a while... i wen to my itunes and tried selecting a song i have nothing played the song said it was playing but the time wasnt moving it was stuck at 0:00 on both play mode and pause mode (sorry that was my best way to put that into words) i checked itunes volume and my volume on my computer;; i pressed the sound (increase) button on my keyboard when i did that it made no sound like it usually does i even pressed the decrease sound button and nothing happened and i pressed the mute button and nothing happend... when i press any of those sound buttons it has a quit/mute symbol below it?? i pressed the mute button and i pressed the increase sound button i pressed all sound buttons possible and i tried playing a whole bunch of other songs that usually work.... what do i do???? i went to system prefrences>sound;; and it just confused me it said it was on mute but i dont know why i couldnt change it manually either it was a grey checked box for mute and would not let me select it.. PLEASE HELP;; thank you

• Answer:

  If this is a late model G4, check the audio out jack. Do you see a red light coming from it? The optical audio switch may have become stuck. Did it only give you the option for Digital Output in Sound? If that's the case, shut it down and dip a QTip in high-concentration isopropyl alcohol. You may have to tear a little off the end to get it to fit, but twist it into the headphone jack and get it all the way in there. This will clean out any crud that may be sticking the switch. It sounds odd, but I've done this before to solve this exact sort of problem before. If that's not it, it's probably a toasted audio board.