Cambridge 302 blank screen

Has anyone seen this behavior? This has happened twice this season for
the first time in four years of use.

The home screen goes blank during flight. I press the control knob and
the 302 wakes up but not with the normal power up. Instead the display
indexes to the next screen as during normal operation. Yet the flight
logs from these episodes show an interruption in recorded fixes.

No major problem - yet - so I wonder if the problem can wait until the
end of the season.

Mark