RNS 510 sat Nav URGENT!!!!

[ianjmo]

Hey,
I have a 2009 b6 Highline 2.0 TDI Cr DPF.
Just fitted an RNS 510 version P, manufactured in Feb 2014. I've just fitted it to my car, only when u take the key out, you can hear the unit quietly whirring n it will turn on without the key in. Does this mean it's gonna drain the battery???
I've heard it does this on earlier cars but thought a 2009 would be ok. Can anyone let me know ASAP please cos I gotta go out n don't want to go back to the car with a dead battery. I have got time to take it out before I leave. Can someone please advise me....