OK, that would drive me insane too! Whoever owned mine before I bought her must have had that done already because mine has never beeped at me... Same with the 'fasten seatbelt' chime. I have nothing but the dashboard light to remind me. When I had the RDX, it would have a nice female voice come over the speakers asking you to 'Please fasten your seatbelt" and if you ignored it, it would chime constantly and annoyingly. Needless to say, it sure made me fasten my seatbelt!
I hope someone can help you with your 3X door beep ! Actually, I find it fun to look - so I will try too.
- OK, edited to add... I searched the manual by keywords and only found one reference to beeping / chiming 3 times. Not sure this would apply to your situation or not?
"Symptom:
When closing the door after getting out of the vehicle:
The NO KEY warning appears on the display, the outside chime sounds 3 times and the inside warning chime sounds for approximately 3 seconds...
Possible cause:
The ignition switch is in the ACC or ON position."