Other things to try:

- Make sure the analog cable is not plugged in.

- Unplug the USB, turn it off, unplug the brick for 10 seconds and then turn it on again. If the LED is blinking, it's a firmware initialization problem. If the LED stays on, plug in the USB. If the LED now starts blinking, it's a comms problem.
A-LFR/1000-8/500v4x2 coming
100,160,QS10x2,800,M5,M3,M50 v4
had v2
Air N2 (someday)