Hi Damien,
Sorry, but the tagging of audio out pins was made by Lehrian above in the thread - I just edited them in. But to zoom in on the problem at hand: the documentation for the P5534 only mentions existence of audio out, and the pics of the (expensive) cable only shows DIN-jacks for audio in/out (below).
One way to test the rig could be to test the following permutations: A. Both audio out (9, 10) connected to GND + signal in (left or right) on a pair of headphones. B. Pin 9 and GND (14) connected in same way to headphones. C. Pin 10 and GND (14) connected in same way to headphones. You could probably hold the wires to the 3,5 mm male plug of the headphones, just for testing. Pick the working combination.
But if you get audio out, what is really the problem - curious here...
View attachment 226132