At the end of the day it is a basic handheld GPS and it is to be used secondary to DR navigation. I.e a backup. My handheld altimeter overreads also. Besides whats wrong with the Altimeter on the aircraft, last time i checked it is that altimeter which feeds info to the transponder for ATC not the GPS.
Does seem odd though that Kunnas is not there? Most strange. You do have the correct database i assume? Pacific database i think, i can't remember now.
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