registered on this forum to confirm the fix for any awful sync errors for MusicBee ->> Android:
-uninstalled MusicBee and used CCleaner to clear all temp files/folders, cleaned registry
-reboot PC and Android device, reinstalled MusicBee to newest available version
-changed my phone music folder from "Music" to "MusicBeeMusic"
-changed MusicBee synchronization settings for playlists from "pla" type to "m3u"
everything works just as it used to!