The other day I tried to connect my PA-1 MP3 player to the back of my Pioneer head via an RCA -> 3.5mm cable. I don't think that there's a specified auxiliary input for this type of thing, but I noticed that the face had an unlit 'MP3'
space on it. When I got to the back, I found two sets of red/whites - one labelled F and the other SW, undoubtedly Front and Sub channels.
When I plugged the PA-1 into the F set, I could play it through the stereo, but I had to play it in the background. There are normally two 'source' modes, one for the Tuner and one for the CD. If it's set to Tuner, I can hear the Mp3s over the volume of the radio station. If it's set to CD, then I can hear it in addition to the tracks (if there's no CD in, then I can't switch out of Tuner at all). Also, I can only turn the volume of the player off or on from the head unit (by setting the volume to 0 or 1+), although I can adjust it fine on the MP3 player itself.
I don't know how safe this is, since I can only surmise that I'm pushing a signal through an output. I've not played it for more than thirty seconds, just to test it, so I haven't done any damage yet. Does anyone know how I can wire it in safely, or if that's even possible with this unit?