Docker-ORS Hiking Elevation Data


I need to run a customized instance of OpenRouteService with Docker. I have built it from source and it is up and running with an OSM map for Austria - I need ORS to route hiking trails. This is working, but the elevation data is very inaccurate (especially, I need the ascent and descent values to be as precise as possible) - on the official hosted API, the values are very accurate. What elevation settings must I use to get the same correct elevation data on my self hosted instance as with the hosted API?

Thanks a lot!