I just fixed mine after reading another thread. Basically, you will need to choose when to clear the local data and sync from scratch. The risk is you will probably lose flight records. I did this and only lost my last flight record. Perhaps it was corrupted? I don't know. Started having the sync problem when I started deleting 0 distance flight records (ie. Power up but no flying). Glad I did it now be potentially losing a lot of newer flight records.