I'm flying an mRo PixRacer R14 with an mRo uGPS ublox SAM MAQ (https://store.mrobotics.io/product-p/mro-ugps-samm8q-01.htm), and the Estimated position keeps returning to the home location during flight.
For a typical example, see this flight log: https://logs.px4.io/plot_app?log=14d3f981-f8b2-437a-887a-cdac2d9df56e
I've seen similar things happening with an mRo GPS u-Blox Neo-M8N + HMC5983, but I don't have any logs for that handy. They basically look the same, even though the vehicles themselves are totally different.
I've checked wiring, and have tinkered with adding caps, etc. to try and squash noise. The only thing I haven't tried is running the whole FMU system on an isolated power supply, which seems extreme...
Anyone have any ideas?