3.5mm plug in dash with switch?

Hello all,
On my 2002 RR v8 there is a 3.5 lead & on/off switch next to the flip out cup holder thing.
Is this for audio output from your iPhone etc & if so how do I make it play through the speakers as I cannot see a way to enable it?
I have a parrot blue tooth could it be something to do with that?
Thanks again :mil88:

Defo not standard fitment me thinks.... :nopics:

Any ideas? Thanks for reply Saint .

Could well be an aux in

Try putting a cd into the 6 cd autochanger
Play that cd trough the stereo

Plug in your MP3 player into that 3.5mm socket and turn on that switch

As above....

The usual and easiest way to get MP3 player to play in the L322 was to splice into the audio out cables from the CD player....

Maybe this is a spliced in lead and the switch switches the audio signal from either the CD player or the MP3 jack!

as above just select cd & switch it on

You beauty's . Flicked the switch with cd on & phone came to life. Thanks all really appreciate the advise.
Can anyone reccomend a docking holder with charging & 3.5mm output for an iPhone 5 which looks tidy as hate cables trailing. Links appreciated.
Thanks again all, my son especially appreciates it