Single Parking Sensor R/F constantly malfunctioning.

Has anyone else been having similar parking sensor problems?

My 2010 S80 T6 has factory front and rear parking sensors; the front right parking sensor (no others) malfunctions all the time and displays/sounds like I am 6 inches or less from an object even when there is nothing anywhere near my car (front or rear). In particular it is worse when the car is in reverse, like backing into my flat/level driveway.

I have asked 2 different dealerships to look at it on 3 different occasions (7,500 mi, 15k mi, and some warranty work at 18k mi); all 3 times they have said there are no codes coming up when they test it. They said they can physically replicate and see the problem I am having, but it's not showing any error codes. This last time, I tried insisting that was not the way the system was designed to operate and they need to either replace the front right sensor or the entire parking sensor control module; but they said without error codes they can't replace anything under warranty.

I am trying to find out if other people are having/had this same problem before I contact Volvo Cars North America to get it finally repaired.