Thanks for posting the Gaia 2.3.9 update, including TweenLite 7.0.1 for AS2. Unfortunately, I'm still having problems with SoundAsset.fadeTo.
I've posted (too big to attach) a small test site built with Gaia 2.3.9 that demonstrates the problem:
http://clients2.jdgcommunications.com/gaiatest/gaia_2.3.9_test_site.zipThe page at index/nav/main has a SoundClipAsset that is supposed to play and fade to volume=10 when transitionIn is called. It plays but never fades. If you replace TweenLite.as with TweenLite_6.2.2.as (I've included it in the "gs" folder), delete ASO files, and recompile everything, the sound fades as expected. (The same thing happens with a SoundAsset in MP3 format.)
I've also included a small test of TweenLite (7.0.1) on a MovieClip's volume independent of Gaia: see "tweenlite_test.fla" and "tweenlite_test.swf" (these are in the project "src" and "deploy" folders, respectively). This seems to work OK.