Problems exporting GB2 songs to iTunes/equalizing volume

Question

I’m posting this in both GB and iTunes becuase I don’t know where the problems lies.
1) I’ve exported five tunes I created in GB2.
a) Average length of song is about 3 minutes;
b) Volume settings were pretty much the same. I deliberately set them as close as I could. Especially the Master volume;
c) Average composition of songs is: 3-4 green (MIDI) tracks and 2 or 3 blue (Digital or “real” instrument tracks;
d) All volume settings in iTunes were the same.
When I exported them to iTunes, they were all “Bounced.” To the best I could observe...difficult because the little window just flashed a message under the “Bounced” message, reasons were “Unknown Album Artwork,” something about “Volume,” and another reason I coundn’t decifer.
However,
It appeared iTunes really did accept these songs. They were listed as “Bounced,” “Bounced 2,” “Bounced 3,” etc.
When I played them back, they sounded alright. So, I typed in the acutal name of the songs (By deleting “Bounced” and typing) and put them into the playlist I wanted.
When finished, burned a CD. However, the audio volume of the songs did not equalize. I did, indeed, ensure that the “check volume” button was checked in iTunes. But when I played back from the CD, volume levels were clearly not equalized. (I know iTunes will not perfectly “equalize,” but these are obviously out of whack.
Bottom line: It is going to be very difficult to burn a CD with volume levels for every song jumping all over the place.
What’s wrong and how do I remedy this?
Addendum: I have an iPOD mini. When I play songs from any given playlist, volume is also a problem. One song is at a given level, the next much louder, another much softer.

Answer 1

skip down to the bottom of the Mastering answer:
http://www.bulletsandbones.com/GB/GBFAQ.html#mastering