What does the display of a white Apogee logo "A" on the top panel OLED indicate? Chris February 23, 2021 02:22 Updated The white "A" indicates that USB is disconnected. Connect USB, try a different USB cable or a different Mac USB port. Related articles Power Supply Information: Duet 2 How do I reset the Duet 2 or Duet for iPad & Mac? Can the brightness of Quartet's Touchpads or OLED screens be adjusted? Is Duet compatible with Mac OS X Mavericks (10.9)? Why can't I connect my Duet 2 or Firewire to iPad? Comments 0 comments Article is closed for comments.