My suggestion is to try replacing the pen tip (nib). This prode=uct shoudl haev come with 3 replacement nibs and a small metal nib tweezer. Simply take the tweezer and use the slight divit in one side of it to grasp the pen tip, then pull the tip out. Soetimes a little force is requiered to get ti out. then put another one in with this same method. :D This sounds similar to a problem i had a while back and I figured out that this was the cause. I hope tis helps!
I would recommend turning the Power Saving features OFF in the Device Manager for your tablet. On your computer click on Start, Control Panel, System, then the Hardware tab, then Device Manager. Now find the CyberTablet 6400, right click and select Properties. Click on Power Management and be sure that "Allow the computer to turn off this device to save power" is UNCHECKED. This way the computer will not shut it down when you haven't used it fo a while. Hope this helps. Good luck.
Usually answered in minutes!