Position Drift in Outdoor GPS Flight (non-VIO)

[blakekrpec]

I am attempting to fly the VOXL m500 outdoor using GPS without VIO. Sat count usually gets up to around 16-18 with HDOP ~0.7 VDOP~1.0. I get a valid local position and can fly in position mode, however I am experiencing large amounts of position drift (~3-5 meters along all 3 axis). That is after start up, while the vehicle is sitting still, I can see the values in LOCAL_POSITION_NED changing as if the vehicle were moving. I used the parameter set recommended in the parameter helper file for outdoor GPS flight with no luck. I also have tried tuning EKF2 with no luck. I booted up the vehicle in multiple different locations to see if something about one particular area was the issue, but the drift occurred regardless of location.

Do you have any recommendations where to look next? Unless I missed a parameter somewhere I am at a dead end in getting this resolved.

[blakekrpec]

Here is a link to my .param file: https://drive.google.com/file/d/14DA0fQ8Q4PowwlFXMUfU_w1wteXpM9rk/view?usp=sharing