GarageBand files import with varying volume levels
I record large multitrack projects on GarageBand (both kinds, 6.05 and 10) and strive to get a consistent output level for all of them. But when I export to iTunes there are sometimes huge discrepancies between them in volume. If I reduce the overall level in GB of a given track and re-export it, I find it comes out with the same (undesired) level in iTunes anyway. I have assumed for years that this is an artifact of whatever normalizing process iTunes uses, but I can't find any way to override that. It's quite frustrating---there's no way to get an album's worth of tunes to come out with consistent volume levels. Any help here?
iMac, OS X Yosemite (10.10.2), null