10 Replies Latest reply: Dec 21, 2013 3:09 AM by diveactive
jazzpiano Level 1 Level 1 (0 points)
This is really weird, and I've never seen anyone have this problem.

When I play a CD in my Macbook Pro that has stereo separation panned hard Left and Right, the instrument that should only be in the left channel is in the right as well (but to a lesser degree) the reverse is true for any instrument panned hard right.
When I play the same CD on my CD player these signals are not in any crossing over to the other channel.
I have already check the UNVIVERSAL ACCESS panel and have unchecked the "PLAY STEREO AUDIO as MONO" option.

This is important because PLAY ALONG CD's for musicians are mixed so that if you turn the stereo playback hard right you lose the piano track (hearing only the bass and drums in the left channel, and if you turn the playback hard left you lose the bass, (hearing only the piano and drums).
If you're pianist you practice with the piano track missing of course, if you're a bass player you practice with the bass track missing.

Needles to say, files imported into itunes have this mixed up stereo leakage problem.

Any one have a solution?

Macbook Pro, Mac OS X (10.6.6), Macbook10.4.10 DESKTOP10.4.11
  • 1. Re: Stereo Separation BAD! ow to fix
    louie Level 4 Level 4 (2,945 points)
    Interesting. Does this occur with the built-in speakers, with headphones/earphones, and if you plug external powered speakers into the headphone jack?

    I'd conjecture that there's a crossfeed circuit to make headphone listening more pleasing, but there should be a way to get clean output.
  • 2. Re: Stereo Separation BAD! How to fix
    jazzpiano Level 1 Level 1 (0 points)

    It occurs in all cases that you listed. (very heard to tell about the built in speakers however) because you really need to islolate the left and right ears to be sure of the problem.
    But wen I use externally powered speakers (my stereo) the leakage is there when i pan hard left and right, and when I use the headphone directly into the mac 3.5 mill jack and pan left and right in the *sound control panel*

    But the issue does not happen on my wife's Macbook.
  • 3. Re: Stereo Separation BAD! How to fix
    agrarian3 Level 1 Level 1 (0 points)
    I have had this problem on my MacBook Pro only when using the built-in speakers. I was playing an mp3 file that was specially produced with one instrument only on the left channel and another only on the right. When playing through the laptop's speakers, I can pan all the way left or right and there would be no difference - both instruments could be easily heard. When I did the same thing using headphones, then the Left/Right separation was correct.

    This sounds like a problem with the hardware. I may need to return it on it's warranty.
  • 4. Re: Stereo Separation BAD! How to fix
    jazzpiano Level 1 Level 1 (0 points)
    Unfortunately, my Macbook is long past the warranty.
  • 5. Re: Stereo Separation BAD! ow to fix
    Dave Swan Level 1 Level 1 (5 points)



    I had the exact same problem.  I create backing tracks for my band with the click panned hard left and music hard right.  iTunes was killing the hard panning.  The cause:  Sound Enhancer. 


    Go to preferences > Playback and uncheck SOUND ENHANCER.  (Sound Check is fine).


    Problem solved - well at least for my ears!


    Hope this helps.



  • 6. Re: Stereo Separation BAD! ow to fix
    jazzpiano Level 1 Level 1 (0 points)

    Hi Dave,


    Thanks for your suggestion, however I have had  SOUND ENHANCER unchecked through all this. Apparently there is NO solution to this problem. Pretty weird... I wonder if Apple is aware of this problem.

  • 7. Re: Stereo Separation BAD! ow to fix
    peterhutchau Level 1 Level 1 (0 points)

    This may not be the problem but if you've imported your your tracks from CD, in the advanced or custom encoding setting in iTunes, using 'Joint Stereo' as the mode for stereo could potentially cause this problem so that would be worth checking.

  • 8. Re: Stereo Separation BAD! ow to fix
    FarhanZameer Level 1 Level 1 (0 points)

    I'm having the same problem now. I'm a Sound Engineer, the left side is quite low. And it's not just on iTunes, it's overall. I think it's something with audio jack, I've checked it on multiple headphones.

  • 9. Re: Stereo Separation BAD! ow to fix
    fane_j Level 4 Level 4 (3,660 points)

    FarhanZameer wrote:


    I'm having the same problem now. […] the left side is quite low

    Thread is a bit old. Whatever the OP's issue, you may have come across a design flaw in MBPs. (There are several threads about it.) What Apple is pleased to call a subwoofer is located on the right side of the laptop. So for freqs roughly between 160Hz and 1kHz the balance is off to the right. Freqs above 1kHz should be more or less centred.

  • 10. Re: Stereo Separation BAD! ow to fix
    diveactive Level 1 Level 1 (0 points)

    Hi every one. The problem is gutting, From the day i bought my second mac book pro , I have been trying to get it to sound like the old one, , I was proud to own a mac, For the money spent, Only to find out we have had the wool pulled over our eyes, and struck with a bad deal, I’m on to consumer affairs, and consumer rights, I will keep bugging till they call this problem in for fixing, Sadly getting hold of Mac head office, like most big boys to day , they go round in circles, With other country adress that none hold or want to adress the issue, A stratagy i think to put you of, So you get tired of trying.  Who is the head of Mac?  where is the contact info. An E mail address would be nice. And some true cusomacare on isuse like this and the opticle drive only burning some MLDVDs. A resolve, I know this site is not to do with apple them selves, however we are all in the same boat. If you get this Apple , Please to the Honerable thing, And fix these isues. Is Un fair!


    What your up against, has nothing to do with the stereo control, sliders, Enhancer , or software, Its a design fault from apple mac, They stupidly stuck in a so called extra speaker and called it a sub woofer. OMG crazy, Don’t they know anything about music out put, OK they gave us fiber optic out put in the ear jack,  You need to get toss like FO connected to the Hi fi, Amazing sound, But for portable listening , The sound out put from the internal speakers , SUCK!  Its all right sided, and little if nothing on the left.


    I have asked can mac disconnect the middle speaker, NOT or no one on the net has found a fix, If you do let us all know,