Background hiss and noise when using earbuds on MacBook Pro

"I have the same issue on my 13"", and the solution for me was to change headphones.

The noise is audible over phones with very low impedance. When I use those I can hear the click and noise you describe, very clearly even at low volume. When I use phones with high impedance the problem disappears, even at maximum volume.

I don't think this is an issue with our mabook pros, I think they are all like this. The audio interface is not primarily made for earbuds, perhaps? Find some high impedance phones and give it a try."

"I had the exact same problem. I found this thread: http://forums.macrumors.com/showthread.php?t=329183 and they recommended the Shure Level Attenuator Volume Control EA650. You can find it on Amazon for $20 which, IMO, feels like a ripoff.

However, it actually works. I use it constantly. It's the only way I can listen to music on my MBP without a ringing in my ears afterwards."