and the car kit's little speaker

Wait, I thought you said you wanted the audio output from the telephone to go into the car stereo speakers. That's different than using the speaker that comes with the car kit.

If you just want the empeg to mute when a call comes in, you don't even need to do the special hijack features, the phone mute is built-in by default and is configured through the "configure player" screen in emplode.

Edit: Looking again, I just noticed that I replied to two different people, rather than the same person twice. Clarification noted above is still useful for posterity, so I'll leave it.