Without knowing anything about your actual sound configuration this is not going anywhere.
Shorten your timeline/comp length.
It was happening to me, I had a 4 hour comp because I had pasted something from Premiere without pasting in place. I shortened my comp to the 2 minutes I was actually using, it works now.
I figured to out because I opened the same project in CC2014 and the error message is a little more specific. Something about not enough RAM to render that much audio. You could also maybe adjust the Rage in the preview settings, but I haven't tried that.
The PROBLEM is QuickTime. Quicktime was not installed on my pc, no problem with AE. After installing QT i found the problem about audio memory. After uninstalling QT after effect returned to normal status.
I'm using AE CC and i've downloaded the latest version of QT.
So, this is a very big bug, and after some years Adobe still not done anything to solve it.
QuickTime 7 works pretty well with AE. QuickTime X does not.