>maybe use a multi-track recording software and then adjust each speaker's track to match volume.

Or just a compressor/limiter on the whole shebang will do a good job of normalizing the audio levels.

http://auphonic.com/blog/2011/07/25/loudness-normalization-a...

http://www.hometracked.com/2008/04/20/10-myths-about-normali...