I'm starting to think I have a faulty remote. EM1 is related to some kind of magnetic interference. The error happens when the remote is inside or out, near the quad or not, hooked up to the cell phone or not. Even when the remote is sitting in the middle of a field all alone with no EM of any sort nearby.
The controller appears to work just fine but keeps on displaying the error "Stick EM1" all day every day. Annoying but apparently not fatal. That is not fatal until it is fatal and my Mavic slams into the dirt at 200mph. Will that ever happen? No idea.
At this point my options are to wait for disaster or call DJI and get the royal run-around the are so famous for. I'm not a fan of recalibrating my IMU, banging my drone on the table, dance naked on the lawn, reformatting my computer, downgrading to Windows 95 and all the other garbage things they will suggest before they admit the remote is messed up. I guess I could just be on hold with them all afternoon and PRETEND to go through all the useless steps they suggest.
But then what? Do I really want to send in a working Mavic and get back one that's been smashed up and "refurbished" just because of a random message on the remote that doesn't appear to be causing problems?
Arrrgh.