If you have the newer opener with the "rolling code" system, it's nearly impossible to get false openings by someone else's remote.

If you have an older unit, someone nearby may have set their DIP switches to the same settings as your own. But that would mean someone nearby purchased an old unit...hardly likely.

So I think what others had said about the sensors and pressure adjustments is probably on the mark.

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2009 ML350 (106K) - Family vehicle
2001 CLK430 Cabriolet (80K) - Wife's car
2005 BMW 645CI (138K) - My daily driver
2016 Mustang (32K) - Daughter's car