What software do you use? I believe the Brother software can output it to Adobe or something, you can manually adjust it through there. As for it auto-adjusting, I don't think their software does it, and yes, I have the same problem. Try using other software, or just take the extra minute to manually adjust to your liking.
Not sure on what software name but I reloaded the mfg. disc from the old scanner I had 4years ago...
Works well with windows 8 and my adobe acrobat pro Just be careful if you intend to travel with this scanner alot
never try to see how many a minute... but do plan on buying acrobat pro or something to transfer and print multiple pages when using this scanner. Did use and scan 35 multiple pages for expenses back in Sept this year
I have said it before and I will say it again if you travel with this like I do, protection of this product is Paramount.