Soundgate says that they provide a device that allows control of Sirius radio using the Prius radio controls. Here is their comment, "With our Kenwood interface, you can install a Kenwood 6 or 10-disc CD changer, Sirius Satellite Radio tuner, or both, and control them directly from your factory radio. "And with our Pioneer interface, you can install a Pioneer 6 or 12-disc CD changer, Pioneer XM Satellite Radio tuner, or both, and control them directly from your factory radio." See their page at: http://www.soundgate.com/products/cd/toyota.htm If you click on the "What fits my car" link, they list the 2004 Prius as being supported. I don't know anything about Soundgate. Does this seem legit to those of you who have heard of them?
Big Disapppointment Here is the reply I received when I contacted Soundgate. "Ernie unfortunately that is very old info on the website and hasn't been taken off yet because its going through a complete new design as far as i know there is nothing in the aftermarket for your cars they are completely diff than the rest of Toyota's line up because of the gateway ECU they use. "Sorry for the confusion."
That's too bad. I preferred Sirius over XM. I prefer their music channels I guess I'll wait to see if someone will come up with a way to interface the Sirius receiver with the Prius.