My left hand exhaust seems to keep settling down towards the bottom of the opening. If I adjust it stays in position for a day or 2 then drops back down.
It just looks a bit rubbish from the rear with one pipe lower than the other,
Not because of this, I took the rear grille out completely as I was going to use a more "open" mesh to increase airflow through the rear clam, in the end I liked the look without a grille!