High Sierra 10.13 Mid 2010 Macbook Pro Only 1 boot partition: "Macintosh HD" APFS No Boot Camp No firmware password No FileVault Yes Automatic Login enabled Priority: Not urgent, but is a nuisance Problem: Reboot or Power ON results to default booting into Startup Manager after the "chime sound"... 100% every time. Have to select "Macintosh HD" every time. Attempted: Cleared NVRAM & SMC. Checked faulty OPTION key. CONTROL clicked "Macintosh HD" in Startup Manager. High Sierra > System Preferences >Startup Disk > Selected Macintosh HD MacOS, 10.13. sudo bless -mount "/Volumes/Macintosh HD" -setBoot Not yet attempted (Last resort) Reformat entire SSD, and clean install Anybody encountered such a glitch before?