AC3 file massive size in DVDA. 170mg turns into 7gig!!

[clhomme]

I'm losing my mind.

I'm using Sony Vegas 11.
I render my video as required. Render file comes out at 4.2g.
I render the audio separately as AC3. Render file comes out at 170mb.

When I put them in DVDA, the video file is still 4.2g, but the audio is reported at...