oh yeah I get what i'm supposed to do. I did it on the first try but I guess I got really lucky because after that I couldn't get past it. It got synced for 2 seconds or so before going out of sync again.
basically it went like this : X axis synced for 2 seconds but then was out of sync again (too slow) so I adjusted the slider 1 pixel to the correct direction, then it was in sync for a couple of seconds again before going out of sync again (too fast). so I kept going back and forth and going out of sync