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Post Answer MacBook Pro 15" Core 2 Duo Models A1260 Hi, after lending my macpro to a friend for usage for projection in a large auditorium. It came back with no sound coming out from onboard speakers, system preference also indicated that “headphone” is the only output. If external speakers are attached, the sound is ok. I suspect the left i/o card is damaged. Pls advise on which part/s to buy so that i can start the repair. Your website is a god-send. Too bad, i only chance upon it after ordering another new macpro : ( Thanks Mate!!
Unplug the headphone and go to system preferences -> Sound -> Output, click on the line out, also make sure the mute box is not checked at the bottom. Also please list what options were under “Choose a device for sound output”. In case we have to go further, what system are you running?
I have the identical Model MBP with the identical problem. I’ve received varying advice, mostly to do with inserting a QTip or a toothpick into the headphone socket and finding a small switch that’s supposed to dwell within. Apple are useless on this question - they say they’ve never heard of the problem, which I find hard to believe since I found a forum on another site the other day and there are no less than 78 other people complaining of the same problem over the past 2 years. I’ll add my question to this problem - is there a technical fix for it?
