I recently upgraded my D10A firmware from 4.0 to 5.1.1. Now the compass display is erratic and usually way off (internal - no EDC 10A yet), the CDI is missing from the main and HSI pages (it's selected "on"), and the horizon display is sloppy and slow to react. The Garmin 296 is talking to the D10A because I show GS and ground track on the HSI page. I haven't tried a new mag cal yet. Do I need to disconnect the backup battery for a cold reboot? I backed up the firmware so I can go back if I need to. Ideas?