Overshooting LPV Approach

[flightsimmer33 0]

I use the GTN 750Xi connected to a Baron B58 and X-Plane 11.55. I have connected the GPS to the HSI.

When flying an LPV approach, e.g. to KSEA RWY34C, the Baron overshoots the glide path constantly - I can see this by looking at both the HSI and the dataref gps_vdef_dot as shown in the screen shot below. The autopilot indicates that the approach mode as well as the glideslope mode is coupled/active.

Is there some configuration missing on my end.

24/04/03 14:28:51.063 13784 -    ] # win.xpl version 2.6.1.0
24/04/03 14:28:51.063 13784 INFO ]
24/04/03 14:28:54.679 13784 INFO ] using GTNDBFILE = "D:\Garmin\Databases\nav_db2.bin"

24/04/03 14:28:54.302 13784 -    ] # rxpGtnSim64.dll version 2.6.0.0
24/04/03 14:28:54.301 13784 INFO ]
24/04/03 14:29:08.919 13784 INFO ] using: D:\Garmin\Databases\nav_db2.bin
24/04/03 14:29:09.776 13784 INFO ] GTN 750.1 - TRAINER 6624
24/04/03 14:32:27.622 13784 INFO ] using: D:\Garmin\Databases\nav_db2.bin
24/04/03 14:32:27.667 13784 INFO ] GTN 750.1 - TRAINER 6624
24/04/03 14:32:36.521 13784 INFO ] FPLN not found in: C:\Program Files (x86)\Garmin\Trainers\Packages\GTN\Bin\

 

 

[flightsimmer33 0]

Higher resolution screenshot: