The book says to PRESS AND HOLD the button above the "Detach" button - it does not sound like you are doing that. Seems like you are changing the setting, but not SAVING it.


If pressing and holding that button does not do it, and the display does not 'remember' itself, I would question the power wiring.

The RED wire must be connected to a source that goes dead with the key off.
The YELLOW wire must be connected to a source that stays on all the time - even with the engine cranking.

I can't help you with the iHeart question, (and, perhaps ironically, I work for Kenwood!)