Is it the one right at the bottom of the grade?
A turnout on any kind of an incline no matter how slight is asking for trouble.
I would try modifying your track plan to get that turnout further away from the grade so it is totally flat.
I have no grades on my layout but I still sighted down the top of the rails to check for dips and/or rises and eliminated them with track screw adjustments of shims where necessary.