Timeline cursor always slightly behind

Hi, it seems that whenever I jump to previous or next keyframe the cursor is always slightly behind, rather than on the keyframe, though it acts as it is, also if i make a new keyframe, it also is made slightly infront of the cursor. this makes animating difficult.

Also when I animate, the armature finishes moving, only when the cursor has passed the keyframe, so i have to pose a few frames ahead, or the timing will be out