Please be more specific! Operating system, audio hardware, what audio file is used, how long is the audio and all that. You could run out of memory because the clip is simply too long, you could have an issue with compressed audio formats. nobody can say that based on your insufficient information...
OK, Dell E6400, 2G ram, 500G HD
Mobile Intel 4 video. SO I had read that Roxio CD creator sometimes interfered
with AE. Uninstall, up memory usage prefs for AE and all's well. Reinstall Roxio since I
need to burn a DVD and neither works now.
So, the question of the day is, Does anybody know what CD/DVD burning software can I run on a PC that won't interfere with After Effects?
Nero, Gear, Fireburner. For DVD burning, you can also simply use DVD ripping tools, as they often have their own engine (assuming you already have a working DVD data folder).