Strange phone ringing type noise!

[davegreg]

Driving home tonight, not far from home, i suddenly heard in my car what sounded like a mobile phone ringing....sounded like it was coming from in the boot. Having just picked up a clean bag of laundry i imediately thought i must have somehow ended up with somebody's phone, but when i checked there was nothing there!
Now, i know that the car has a tracker fitted - it was on when i bought it - but i know nothing about the device, don't even know whereabouts on the car it is! I was wondering whether it could have been this making the noise today, because it does make other bleepy noises when you're near speed cameras.

Either that or the car is haunted!

[Well_Fans]

I use rac trackstar with the speed camera database upgrade - I get beeps from stereo as I approach fixed cameras or the average speed limit at specs cameras