Update to my previous post on this thread.
Early RD4 Radios only had ONE active AUX input. If you already have the Bluetooth Hands Free module installed it will be using this port.
This means that there is no available AUX 2 input for adding the ability to stream music from your phone through the Radio !!
Later RD4 Radios (with two aerial inputs) had TWO AUX inputs available.
What is strange is you can program both AUX inputs with DIAGBOX even though the AUX 2 input is not present in the hardware !!
Taken from another thread on this subject (In French) !!
The manual (that comes with Peugeot AUX Cable) covers 2 versions of the Blaupunkt RD4, I am not sure if these versions are what in some forums they refer to as LEVEL1 and LEVEL2. Could be. They differ in that one has, on the back panel, only ONE socket in the lower left corner (like in mine) for the antenna - lets call it LEVEL1 - and the other has TWO sockets, one for the antenna and the other for some other use - lets call this LEVEL2. Both these radios have on the middle right hand side of the back panel, the same socket type for the data and aux cables.
For LEVEL1 RD4 - only ONE aux port can operate, namely AUX1, and it is EITHER allocated and configured for use with the HFK OR the 9706.AG. In my case, I chose to use it with the 9706.AG, therefore I can´t operate the HFK, unless I remove the 9706.AG and go to a Peugeot dealer to reconfigure the AUX1.
For LEVEL2 RD4 - on AUX1, you can configure it EITHER for the 9706.AG OR the HFK. But if you configure AUX1 for 9706.AG, you CAN´T use AUX2 for the HFK. To use BOTH, you have to configure AUX1 for the HFK and AUX2 for the 9706.AG. And thats the only combination, only on the LEVEL2 RD4, that allows both a sound source and a hands free kit to function together.
As for the wiring, and again I say that my manual had NO bugs - as I think all manuals from lately - it goes like this:
AUX1: RED wire (right channel) - pin 4
WHITE wire (left channel) - pin 10
BLACK wire (ground) - pin 11
AUX2: RED wire - pin 7
WHITE wire - pin 1
BLACK wire - pin 2