How to debug "RTT too high for timesync" problems

I was not too sure if this was the right category for the question, please correct if wrong channel.

I am trying to timesync ardupilot running on a pixracer with mavros running on a jetson nx. As of now I always get RTT’s of about ~100ms, which is very surprising. Sometimes the RTT’s are lower, around 50ms and sometimes they are larger, around 500ms. Can electromagnetic interference play a part in this? I have tried running both mavsdk and mavros, and both cannot sync because of too high RTT.

Do anyone have any tips on how/what to debug when RTT too high for timesync appears?

Hey @mathsten
Did you solve the RTT TOO HIGH FOR TIMESYNC ISSUE?
I am facing the same issue with me quadcopter running ArduPilot v4.3.4 while trying to communicate with MAVROS.
Please help!