Elevator trim keeps jumping back to neutral

For quite some time I've been using a Saitek trim wheel for most of my aircraft, but for the ones that use a stick instead of a yoke, I'm using a switch on my Saitek X-52pro.

The trim wheel is connected through the P3D native control setup, while the Saitek X-52 switch is connected through FSUIPC. This always worked just fine, but since a couple of days, the elevator trim in my aircraft keeps jumping back to neutral position, every time I adjust it from the X-52.

Does anyone know what the problem could be and how to fix this?