Unless you have a different bug, "the audio delay for volume changes is multiple seconds instead of instant" was fixed in version 2.0.1 along with several other issues.
The audio delay issue persists for me in version 2.0.1 like the parent commenter. Among other issues is an increase in random crashing. The new interface isn't particularly inviting, either. Reading through the other comments here has caused me to revert to the older version with which I was never unhappy with.
I also see it "rebuilding font cache" on every fresh start. Is anyone else seeing that? Very annoying.
Yea, I get that on any 720p + movie. Basically any mkv that may have subtitle support.