What type of maps?
Have you enabled opengl on raspbian or on opencpn?
Try typing: opencpn -no_opengl
Try deleting the folder /home/pi/.opencpn This will back opencpn to the default state.
Have you enabled opengl on raspbian or on opencpn?
Try typing: opencpn -no_opengl
Try deleting the folder /home/pi/.opencpn This will back opencpn to the default state.