is it possible to downgrade from the 1.6 update back down to 1.3.  sent in my hu for repair and pioneer updated it.  things have not been as good since.  really want to go back.  any help would be appreciated.

thanks

Old topic, but I'd think so. You'd likely need to have the previous version "update", and binary editor, to replace the software version check to rename the old version to a 'newer' version number than currently in your phone. I'd be wary, as if another update comes out, that update may cross-check for 'official' version numbers which are legit, against what is in your system.

You might be the pioneer to discovery.

Run the 2016 map update, and move forward to 3.0 firmware.