high pitch ringing in headphones

In answering this question I'm assuming you have bought headphones recently rather than a new Mac.

There are very few headphones fully compatible with the Mac OS - probably because the makers haven't provided suitable drivers for their products. This issue, not necessarily exactly the same symptom as you have, has cropped up before in these discussions. Check whether the package claims compatibility. If it does then you can start looking for reasons for the problem.

If it's a new Mac, is the headphone driver suitable for Leopard OS?

Neville

My understanding is that most headphones are not automatically compatible with Mac OS, in fact few are. All hardware attached needs some form of driver, mostly included with Mac OS, eg most printers and scanners, or on provided cd. However experience has shown that there have been difficulties with headphones. A couple of years ago I was thinking of getting headphones but could find none in the stores that claimed compatibility with Mac OS, only with Windows. I approached my Apple store & they said they knew of none at that time that were compatible! Check whether Sony claim compatibility, and if so, check for the latest driver for that model.

Neville

I've never heard of OSX needing drivers for headphones, especially when just using the Line Out jack.

The only time I hear any hi-pitched noises coming from my MacBook Pro is when I have the line out connected to an amplified sound system, and if there is an external device also connected, such as an external monitor or FireWire drive. The only way I've found to clear the noise, which sounds like ground interference, is to run the line out to a DI box with a ground lift switch. Such as a Whirlwind PC-DI, Direct2, or Direct2-JT.

I've never heard the noise through just headphones, though.

No, you don't need drivers for them, icrude001. Pretty hard to see how drivers could work for any such device on the headphone socket, in fact! I suspect neville is thinking of headsets that connect through the USB port.

One thing I've seen on Powerbooks in the past that can cause headphone noise issues are plugs that have a metal surround contacting the body of the computer, or that dont fit securely in the socket. I wouldn't expect this on a pair of good Sony's, and I haven't sen it on my MBP, but it might be worth checking.

Other possibilities might be interference from the MBP's wireless options, or from the power supply. Does it it happen with airport and BT turned off and the power supply disconnected?

Cheers

Rod

Message was edited by: Rod Hagen

I was looking for a headset to use with Skype in particular. Perhaps these were usb headsets but I didn't think so at the time as I was thinking the Line Out jack. What I remember was examining Logitech headsets in a retailer's supplies and noticing that Logitech only quoted Windows compatibility. The sales people would not even sell me one of those because I wanted to use it on a Mac! My preferred Apple dealer made the comment that there were at the time no suitable headsets available for use with a Mac.

Neville

Hi neville. The current Logitech "Skype" type headsets I can think of are either USB or bluetooth (and these could have driver issues though you can certainly get Mac compatible versions these days - see http://www.amazon.com/Logitech-980356-0403-Stereo-USB-Headset/dp/B0007ZFM38).

Some PC headphones might have problems because of different hardware (rather than driver) power supply regimes and different output levels through the headphone / line out jack on a mac, though.

Cheers

Rod

Message was edited by: Rod Hagen

OK, It is very easy to reproduce the problem, just follow this steps:

(1) Insert any headphones to iMac.
(2) Do NOT play any iTunes or any application with sound.
(3) Now, set volume with the volume control keys on your keyboard, set it to the MAX.
(4) You can keep pressing on the increase volume key and every time you hit the key you should hear a sound.

Just as when the sound stop, you will hear a high pitch. Keep repeat step 4 and wait a while, then occasionally you will hear a high pitch sound that will last to longer than 30 seconds. The high pitch will be even easier to reproduce if you alternate before decreasing volume and increase volume by 1 level, each time, wait and you will hear the high pitch too.

This high pitch sound can be heard on external speaker plug into the headphone jacks too.

I am going to call the Apple Care tomorrow. Will keep you guys posted.

Thanks Rod. My enquiries were about 2 years ago.

Neville

I have the same problem on my iMac 24" alum. The high pitch is there even with external speaker attached to the headphone jack.

Message was edited by: chienlim