wiring cd player to headphone jacks

Hi -

2000 Savana (Explorer conversion) I had to replace a nonfunctioning rear CD player with a similar model (in this case a Sony CDX-GT110) The existing wiring jack was exactly the same as would go in this Sony.

Here's the question. The wiring from the CD player only goes to 4 head phone jacks located in the back of the van. Those jacks each have a green wire going to the top of the jack box and a grey wire and a black wire going to terminals at the bottom of the jack. The harness that runs from the van, which then connects by way of spade terminals to the individual wires from the CD player, is wired as follows:

There are the standard HOT, ALWAYS HOT, and ground leads, but there is only one each for attaching to the 4 channels of audio from the CD harness. The leads from the CD are all dual (one green, on GREEN/ blk striped, purp/purb/blk stripe etc for all 4 channels) yet there is only one lead to connect to on the van harness. I would have thought then that all grounds from the CD audio channels (all 4 striped leads) would go to the GRD lead from the van harness, but here is where it gets confusing.

The CD harness only has the left rear(grn and grn/blk) and right rear(purp and purp/blk) wires going to the van harness wires - the front channels are unattached (with one exception - more later). However these (green and purp) wires are wired strangely. Using the green set for example, one of the wires is soldered to one end of a resistor. The other end of the resistor is then spliced into the other wire of its pair, and then is soldered to one end of a small capacitor. From the other end of that capacitor it is attached to a single wire (one of those black or grey wires that runs to the headphone jack terminals). 

What is going on there? How do they splice the two wires (green and GREEN/ blk striped) together, run them thru a resistor and capacitor, and then eventually end up connecting to a single wire?? Where is the ground? And if you have a few extra secs, what is the purpose of the resistor and capacitor?

The problem is that when I listen thru headphones via the HP jacks, if the balance is centered, the vocals sound as if they are in a tin can and the whole thing sounds pretty weak. As I move to full right channel, the enttire volume seems to get louder and crisper and I still hear the left side just as loud as the right - only I don't heat a certain part of the song though (for instance the lead guitar perhaps). If I go to full left now, the volume slowly fades as I reach center again and then increases as I go full left. Same thing now on the left side - equally loud on both sides, but now I hear the lead guitar but no rythym or drums etc. Is this a part of that funky 2 into 1 wiring above? Usually when the balance is full one way, you hear nothing on the other side, and vice versa. I still hear both side equally well with the balance full to one side, i't s just that I don't hear a certain part - not volume - of the song instead.

Lastly, I mentioned no front channel wires from the CD were attached to anything. Except one, which was the WHITE/ blk striped wire of the left front channel pair, to the green wire that goes to the top terminal of the headphone jacks. The other white wire was unattached. I was having a major problem with hearing one side only if the headphone jack (stereo) was fully inserted into the receptacle. If I pulled the jack out halfway then I would hear the other side, but still only one side at a time though. If I pulled it out a little further and jiggled it in the jack then I could sometimes get both channels at once, but any bump in the road would dislodge it and I'd only get one side again. This was not correct obviously, so for grins I disconnected that sole white (left front) wire from the green one and voila! - suddenly I get both channels clear as a bell when I fully insert the jack into the receptacle. On all 4 headphone jack panels as well. So what was that one front left channel wire connected to that green wire on the headphone jack terminal for? What about the unused 2 wires from the front right channel?

I know that was a lot of info. I am hoping that you are extremely familiar with the way conversion vans are wired to the headphone jacks and that you have seen this setup before, and that it made sense the way I described it therefore. Hope you can help me with the balance problem..Can I get rid of those resistors and capacitors, and just splice the two left channel wires (one from the front pair and one from the rear pair), splice the two right channels (again one front one rear) and attach one of  these to the grey wire on the headphone termial (which I assume is either the left or right channel) and the other to the Black wire on the headphone terminal (which I guess would be the other  channel then) and then twist all 4 ground leads (the striped ones from the 4 channels?) together and connect it to the green wire of the headphone terminal (which I am assuming - and I'm not sure at ALL on this - is the ground lead to the headphone terminal jack)?  Or do I just need 2 channels (1 left and 1 right from EITHER the front or rear)?

Thanks for any help

Mike

The purpose of the capacitor is to block the 6 volts of DC voltage that is on the speaker wires of any newer radio.  IT IS NEEDED.  The resistor is to absorb some of the power, to not overpower the headphones.  IT TOO IS NEEDED. 

What is the ground of the headphones (the part of the plug nearest the wires) connected to?    It sounds to me that you have no ground for the headphones.  When you balance to one channel the other channel becomes ground.