I have the same issue after upgrading my ROM on Nougat 7.1.1 OnePlus3 with latest OpenBeta. Happens on both iGO Basarsoft 9.18.27.709965 & iGO Navigation 9.18.27.705829. Will have to google more driver option to force. Only difference is that it starts with black screen and then shuts down. Last time this happened, newer version of software sorted the issue. Have already tried un-installing, clearing cashe, deleting Save folder and reinstalling.
Perhaps running full debug may indicate the issue. Will have to Google the debug command for sys.txt. I deleted the sys.txt file that had the full debug log commands when I wiped my system ina n attempt to get it working again :-( (Forgot to back it up)