During a flight last week I experienced two unprovoked reboots of my AF-5500.
Both times the instrument recovered with no input from me, but after the
second reboot there was an annoying "flashing" of the video screen. The incident
occurred at high altitude and very cold OAT (5F). The cockpit temperature was
somewhat warmer, but still quite cold. After descent to a lower (warmer) altitude
the flashing effect gradually disappeared. The incident did not repeat on several
subsequent flights in warmer (and lower) conditions. Any ideas?

One of the things I tried to stop the flashing effect was to reboot the
instrument in flight by turning off the master power. It would not reboot
in this condition, and continued to operate on the backup power. Is
there a magic key sequence to force an in-flight reboot?
Thx,
-Dan