I recently purchased a 2009 Octavia L&K DSG for my wife with the Columbus DVD/Satnav.  It works normally during driving but when I shut off the car or even switch it off while driving I hear a very faint whirring noise.  This goes on for 10-15 minutes after engine is shut off and keys are removed.  No CD in it.  Does not sound like the CD/DVD drive turning.  More like a cooling fan.  Any ideas?  

Edited 10 January, 201511 yr by Skodadrivingamerican

Probably the cooling fan. Mine does the same. Even more if I have had the hvac on hot

Sent from my Galaxy S5

its normal and nothing to worry about, as long as it shuts off after 15mins then there is no problem.

You find a lot of VAG's do this and some do it for a while as said above for anything between a few seconds to 10-15 minutes. Should be fine mate

Had a customer complained about this and it was doing it all the time. Left the car at night time and came back in the morning to find it still doing it. As said, the unit goes to sleep after a few minutes, and then when you unlock the car it wakes up again and starts the fan etc. Only if you're really quick getting in can you hear the unit in it's sleep state and then start to wake up.