Ijust bought the v700 had the same problem. My workout (using Epson Scan):
1. Cleaning rhe scanner glass from the inside. (It's easy to get it disassembled just 4 screws)
2. Using the free version of nik collection. Define.
3. You have the color efex too. There's a filter named Remove color cast, works great.
4. And finally, people don't know that, but you can still ask for the free version of nik collection. Here is the link:
Nik Collection 2012 - Nik Collection by DxO