Try
this link, in the post above it was truncated/misinterpreted by the BBS code, but cut and paste of the
complete url worked for me. The article number is CD-RB10
Description is as follows:
"Auxiliary Input Adaptors
CD-RB10
Auxiliary Input Adapter RCA for IP-Bus Headunits"
To me that's the description of a thing that plugs into the rear of your Pioneer HUs IP-bus connector and gives you RCA inputs.
I have no idea of how the Pioneer IP-bus works, so maybe this would give you RCA out from the XM module, but I doubt it.
/Michael