I know this is old, but I'm replying just in case you haven't found your solution.
I don't know why, but native OpenAL on MacOSX only appears to work in 32-bit applications. If your app is 64-bit, it just won't work. This has been my experience trying to get OpenAL working on MacOSX Snow Leopard (10.6) 2 years ago. So as far as native OpenAL goes, I think you're stuck. I can't find any explanation as to why this is, and rarely have I been able to google anyone with the same problem.
There is one solution however. Try using OpenAL-Soft. It's an LGPL software implementation of OpenAL with a few extras. This solved my issues, and I can now have OpenAL support for 64-bit apps. Works great so far, I even use it for Android.
One final note, Creative hasn't been doing a very diligent job of maintaining OpenAL the way Khronos maintains OpenGL. This is sad, because I like OpenAL much better than the other alternatives in general (except DirectSound, which has been deprecated since Vista killed it). Because of this, some open source implementations like OpenAL-Soft came into existence.
Hope this helps,
EDIT: Link to OpenAL-Soft.framework
Edited by blueshogun96, 06 August 2014 - 02:14 PM.