How far do you have to be from power lines and magnetic warning

[Grumpy]

Was at a friends over the weekend and they live pretty far out of town. Noticed that when I went to fire it up I got TWO warnings, one was a restricted air space warning, the second was electromagnetic interference - I know he has some big power lines not too far from his house. Actually moved away from them, but same thing. Is the compass that sensitive? It basically would not let me turn the quad on with both of the warnings. It actually wanted me to connect to the internet for flight authorization in the "restricted air space". I did not have an internet connection, so I don't know what it wanted for authorization. Anyone run into this?

 

[DanMan32]

If within 2 miles of an airport, you'll get that. You can go onto DJI's fly safe site ahead of time and get a code that you can enter into the app offline. DJI GEO System - Up-to-date Information On Where to Fly
You can also turn off geo in the app general settings but that might revert it to the old system which in many ways was more restrictive.
There could be other sources of interference. Buried metal pipes or electrical conduit for example.
If on a concrete slab, could be rebar in it.