The Normalize button was left inactive in version 8, unfortunately.
Dear Mr. Grisetti,
Apparently, we are not talking about the same program. Using PE8, the "Normalize Audio" option can be selected using one of two methods. The first is to go to the "Clip" menu and choose "Audio Gain" or the second is to select the audio portion in the timeline, right click and do the same. I have used it successfully many, many times (including in this specific production). However, my question has to do with that same function not working on a specific mpeg file.