Recently, I have been getting a lot of these. Seems to have something to do with accelerating at a medium clip. I tried watching the voltage on the detector just before it goes off, but I don't see an increase or decrease. Happens day or night when there are no sources of an alert other than possibly sunlight or street lamps. Hard to reproduce as it does not happen at the same place, same time, every time, even if you try to drive the same way. Very annoying as it makes you want to back off the gas, just in case. It's about 3 1/2 years old and has been treated well.
Anyone got any clues?