Problems with 'new' s4

I recently (a day ago) purchased an s4 from a guy off of craigslist to replace my old vci-100. When i got it home, and after installing the driver, was thrilled with my new piece of kit. however, as i started playing with it, i noticed some interesting problems. I searched the internet and this site extensively for people who might have had the same problem, but i couldn't seem to find anything. Anyhow, these are the issues that I'm having, and any help you guys can offer would be appreciated. First, the master control knob does adjust the volume, but does so with no interaction with traktor: it works like the dial on the side of my audio 2 dj, in that while it makes it louder and softer, the main volume of the program isnt affected at all. Second, the displays in the looping section don't come on at all, but the knobs do what they're supposed to just fine. Third, the sample buttons seem to be working as auto loop buttons with the center two activating 4 bar loops and the outer two 8 bars. and finally, the offset buttons above the tempo sliders do exactly nothing. Other that these issues, the unit functions perfectly, and like i said before, any advice you can offer is greatly appreciated.