Grounding Issue with vci 100
I have a toshiba Satellite M305D that I use with my vci 100 and Audio 4 Dj for Traktor pro 2. I recently bought this from someone on craigslist and tested at his place and it worked fine. But when I connected it to my setup, the platters just don’t seem to work unless I touch some metal surface on the vci. So, I figured this is potentially a ground issue which I cannot find a solution for. I unfortunately not very good at electronics and someone mentioned here http://www.djtechtools.com/forum/showthread.php?t=1873&highlight=ground+issue
that I could ground the vci 100 using the ground connector on my Audio 4Dj.
Any ideas ?? 
This is very urgent as I have a Dj class coming up and I really need my setup working. Would really appreciate any help. 
P.S : I am powering both of them through USB ports on my laptop and have tried using a USB (powered and unpowered) hub too.
Thanks
UB
Have you tried adjusting the jog sensitivity with the dials on the back?
Yes I have tried it. It does not seem to work. I always have to touch the metal surface somewhere to turn the platter lights from blue to red (showing that they work.)
First thing I would try would be to try and tighten the screws on the top plate. If that doesn’t work then maybe connect a wire between the VCI and the Audio 4 and see if that helps.
too bad ! … its not helping. I tried exactly what you suggested but still not able to make the platters work 
Am I the only one in this world to see this issue with this controller ?
So I figured the issue is not with the vci but with my laptop. It worked flawlessly with my friends laptop so i will have to look into a way to fix my laptop. Thanks for ur help photojojo.
Does it do it with your laptop plugged in? You could try a ground loop isolator on the laptop plug. Maybe a good powered USB port?
Also have you tried plugging in the VCI with a power supply?
you have to touch the metal part of the platter for the jog to sense, the outer part is for pitch bend