It is not. Volume leveling is based on Replay Gain.
Matt, are you saying that Volume Leveling is currently using the Replay Gain figure instead of R128? If that's not what you're saying, what did you mean? Your short one-liners are often difficult to understand what you're really trying to say.
I have to agree with the OP, for whatever reason there can still be quite a variance between tracks. Muddy Waters is a good example because it is mixed rather bright (his vocal mostly) and is very annoying to listen to at your normal reference level.
Last week I was experimenting with this trying to find some indication that represented level adjustments that I hear from track to track. By far, the old Replay Gain figure was closer to reality, but either group could still be off track to track by over 6db. My reference listening level is between 83db and 86db, a comfortable level on most well recorded music when played on a well balanced system. But throw Muddy in there, and you *have* to turn it down.
The only way I have found to mitigate this is to listen at lower levels, like around 70db or less where your ear is less sensitive to level changes. But that takes some of the fun out of it!
And forget Peak Normalize for anything, as it frequently allows the signal over 0db reference level and clipping. The only way to get extremely clean audio on everything you play is with Volume Leveling ON, Adaptive Volume OFF, and Clip Protection OFF. Even at that you'll see peak output levels hovering around -6 to -12db, but with some songs pushing up to around -1db at the output of the DSP studio.
--Bill