MAC,
It is an adapter made by Soundgate. It plugs into your truck's wiring between the stereo and the wiring harness. It then has a plug on it that allows Pioneer audio accessories to be plugged into it. These include an XM tuner box, a 6 or 12 CD changer, or another small adapter that has RCA jacks on it to give you an AUX input, like your home stereo. You could plug in a digital music player, for example. The Pioneer accessories would be controlled by your factory stereo.
Unfortunately, these Soundgate adapters have been a disappointment. Lots of problems. In just a few months they are already up to version 3 of the product.
However, there is good news to report. Another company with a much better reputation (Blitzsafe) is working on adapters for GM vehicles like ours. One of the adapters will allow the Delphi Skyfi XM module to be mounted out of sight in the vehicle, and be controlled by the OEM factory stereo. The adapter will be called Skylink.
This is great news, because the Delphi Skyfi unit is portable. You only have to pay for one subscription, and you can move the Skyfi module from car to car, to your house, and even a boom box.
The Blitzsafe Skylink should be available in March or April.
Klaus
Rare 2003 H2 with UM8 Integrated Navigation Radio
Skull & Bones Member since 2003