Currently Being ModeratedJun 8, 2013 3:23 AM (in response to Ed_UK)
Try resetting the NVRAM and maybe a different set of headphones to help isolate the issue. Also may want to make sure it is the headphone jack and not the line-in...only because I know someone who has done that before, but I will not mention any names ;)
Oh and if you have recently added any non-apple hardware, you may want to temporarily disconnect it...
Currently Being ModeratedJun 8, 2013 9:37 AM (in response to jsmnkcmo)
thiank you for your advice i tried your suggestions
... and well sadly no joy.... it just keeeps going giving a wooshing sound and making a
phew vvouhi Phew (imagine a radar gunsound ) pei aww
whats next to try?
Currently Being ModeratedJun 9, 2013 3:38 AM (in response to Paul_31)
i have tried a mixture of headphones / earphones etc still the whosing sound....??? also on the freak occasion it does work the sound is really quiet(despite the volume on full from all programs and the system volume etc).
Currently Being ModeratedJun 9, 2013 4:18 AM (in response to Ed_UK)
Not sure this will work, but it won't hurt to try. Launch 'Audio MIDI Setup' in the utilities folder (make a note of the various settings so that you can re-instate them if necessary) and see if adjusting the settings fixes things. Here's a screenshot of mine and the headphones are working.
Also, if you're using iTunes or something that supports Airplay check the sound settings are set to the computer and not to Airplay to another device.
Currently Being ModeratedJun 9, 2013 6:25 AM (in response to Ed_UK)
I second Rudegar...if you have Apple Care or your iMac is still under warranty...you may want to reach out to Apple Care to see what is going on.
One last thing.... if you hold down option and click on the speaker in the menu bar (with your head-set plugged in, you should be able to choose your output option...
The only time I have had a similar problem, I was plugging it into the output jack vs. the input, but I think you covered that already...
When you get a resolution, I would be interested to see what the resolution is.
@Community, would reseting SMC be of any benefit?
Currently Being ModeratedJun 9, 2013 6:45 AM (in response to Ed_UK)
Can you see a red glow in the headphone jack? If so, an out-of spec headphone plus has jammed the jack's mute contact in the muted position. Plus the headphones back in and VERY GENTLY wiggle them in the horizintal plane. This usually unsticks the contact.
Background, or "why this happens": the audio-out port on a modern Mac is digital and is held to high dimensional standards. Most headphones have an analog plug not made to such standards. The specific issue is the the "tip-to-stop shoulder" distance on many analog plugs is just a bit longer than on a digital one and jams the "mute" contact inside the port in the muted position.
The best action is prevention. When connecting headphones (or external speakers), put on the headphones and have an audio track running BEFORE you insert the plug. Insert the plug slowly, listening for sound on both channels and, when you hear it, STOP INSERTING.
Bottom line is you do NOT want to insert any random plug "to the hilt" until you know it is dimensioned to fit a digital port.
My MacBook Pro has the same jack. I have a pair of decent-quality, name-brand headphones and their plug is not to spec. This picture shows their plug in the port at a position that delivers proper sound yet does not let the plug fall out:
Note that the shoulder is about 1/16-inch from contacting the computer case. It is secure in this position.
Every plug is different. I have a pair of El Cheapo external speakers I picked up for US$2 at a yard sale and their plug fits perfectly on all my Macs with a digital audio port. Go figure!