Some more things to try and test in this order:
- Clear nonvol [non-volatile memory]. It's a little more comprehensive than a hard reset: [Only registered and activated users can see links. ].
- Replace the microSD with a known reliable or new one or move the EUU onto the unit if there's enough space.
- Remove [not just uncheck, move off the unit/card] ALL other maps [detail maps, DEM, 3D Buildings] except your current EUU and basemap of course.
- Replace the basemap: [Only registered and activated users can see links. ].
- Redownload and replace the EUU map.
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