My cat is a 2 year old, very well trained to use the litter box and bury her waste. But for the past week she's been missing her aim at night while she's in her cage. Half her poop would be out or dripping by the box's side. We thought it was the cage issue so we decided to allow her to roam free at night, with the litter box at a convinient spot (the placement of the litter box is not an issue, she's used to the area). But the past two days of letting her free at night has been even more surprising. She poops right beside the litter box. It's not even a few feet away, its literally 2-3 inches away from the box. Any idea of why the sudden change in behaviour?