Hello everyone,
I have the FBW A320nx Custom Version installed and when the Autopilot is engaged, I get these weird up and down oscillations in pitch. For example, if I set the cruising altitude to FL340 with a V/S of +2000 in selected altitude mode, the AP will go up to around 2400 and then down to -300 and then back up and repeat this cycle till it gets to FL340. Interestingly this only happens above approximately FL180. Hopefully the video below will make everything clear.