To Baron and Monkey,
Monkey sounds like you are riding a bit underpowered and are oversheeting the kite (pulling in on the bar too much), this tends to create a stall in the airflow over the canopy and sometimes results in the kite flying backwards or just stopping forward flying and crashing backwards.
When you unhook, the kite will always be powered and you will be surprised at how much extra power the kite generates by you not sheeting out unwittingly as you ride. To set the bar, you should aim at riding with the trim strap pulled in a fair way to reduce the wingtip flaring. Whenever I unhook, I always sheet in about 75% of the trim strap before I unhook and then let it back out again when I hook back in. If your kite is stalling on the upstroke, you have too much back line tension and need to pull in more on the trim strap.
Baron, you are riding hooked in with too much back line tension. The X2's were quite a high aspect ratio kite and were fairly susceptible to stalling if oversheeted. You will get more power from your X2 if you sheet it out a bit and allow it to generate power the way it was designed to .... by flying fast. This is why X2's were never meant to be a beginner kite, they need to fly really quick to generate their power, oversheeting until you "feel" power or pressure is not the way they work and if you "feel" that pressure at low speeds you are way oversheeted.
You are probably riding with the bar a fair ways out from your body if when you are unhooked if it stalls/flys slowly. Try resetting your lines. All 4 lines should be equal length with the trim strap set at full power and the bar at about 30% from full power.
Hope this helps,