Yeah I had that problem before. Your jogging moves aren't working because you were either moving to fast, the acceleration was too high, or a software setting doesn't match your hardware. Sounds like the first. What you want to do is set your minimum speed, acceleration and maximum speed to something you know will work(something real slow). Make sure your software settings match you hardware(step on high signal ect.). Now slowly increase the maximum speed until you start missing steps while jogging. Now back it off 15 to 20 percent. Then do the same with minimum speed and finally acceleration. You do need to back off that much because your machine will move two axes at a time for interpolated moves and it will keep your machine more reliable.
My driver takes 12-40v and when I started I had a 12v supply and max speed of 11ipm then at 24v, 18ipm and now finally at 38v, 30+ ipm. If your not happy with the results after tuning try a higher voltage supply. You should see higher speeds and more heat at the motors.
http://chuckscnc.blogspot.com/