If you're scanning something larger (say a larger image or pages of text) you can take multiple scans of the object and using Doxie's software, stitch the scans into one image. Installed Audacity 2.1.2 on my Mac running OS X Yosemite 10.10.5. I have done some searching and can't seem to see a solution.
Audacity is one of the best audio mixer software.