Connecting Pixhawk Mini 4 to Spektrum Receiver


I have a Holybro QAV250 with a Pixhawk Mini 4 controller, and I’m trying to pair it with my Spektrum receiver. According to the Pixhawk wiring guide online, all Spektrum DSM/DSMX signals should go through the RC IN port on the Pixhawk. There are 2 cables provided for DSMX receivers (shown in the image)

Previously I had a FlySky receiver. I only needed to plug in the servo male plug to Channel 1 of my receiver and the PPM port on my Pixhawk Mini 4 without any encoder, and I could easily perform radio calibration through QGroundControl.

However, it doesn’t work for my Spektrum receiver even though I used the cable with the servo male plug to the RC IN port on my Pixhawk Mini 4.

Do I need to plug it into XBUS or SRXL2 ? To make it even more confusing, theres another SRXL2 port that is the same as the bind port (accepts the standard servo male plug). I’d appreciate any help