There are two methods that act as a work-around to enable the M70 to be used with Traktor Scratch DVS system, without having to use a certified soundcard. With this 'Hack' you will be able to use the built-in sound card for scratch DVD features, just the same as you can with Virtual DJ 7.
METHOD 1: Adding or editing USB device in REGEDIT.EXE (Windows Machines)
Step one: Install your M70 device drivers
Step two: open REGEDIT.EXE from 'run' command. Go to Local Machine/Software/Wow6432Node/ASIO. There you will find the M70 sound card entry. If you like, you can either edit this entry, or Copy it to a new entry.
Step three: Edit the Description by double clicking on 'Description' and typing "Audio 4 DJ" (Or "Audio 8 DJ") in the text box.
Step four: Now you can open Traktor Scratch, and if you typed the Description in correctly you will immediately find the Audio 4 DJ (or Audio 8 DJ) available in the Audio Device List. Select it, and you should see the timecode finctions come to life where it says Phone/Line. Now you can go to the Timecode setup tab to finish your calibration.
There is another Method that is more complex, but very effective. Check out DVS Mode activation (Part 2) - Traktor