Welcome to the world of custom making :D I'll suggest something, you might think I'm mad but I tell you its worked for me a couple of times... Start a blank toolkit and type everything in again, do not use a template save. Also, what's the current state of your game - is it playing other CDLC just now or do they crash too? Also, are you sure you converted the audio properly, did you use Seek Table Granularity of 16438? I did check the project in wwise and they are set correctly. In my OP, I did state that I tried making a fresh project in the Toolkit. Could making a fresh project in wwise make a difference? Also other CDLC works fine. I suppose worth noting is the source of the song file itself. Its a FLAC file converted to an MP3 using LAME from inside of Foobar2000 What if it is too similar to actual DLC? It is a 311 song and they did get a official DLC pack. Should I try to contact those two you mentioned? Again, if I need to, I will upload the source files for someone to take a look at. I'm at a complete loss at this point.