This is a copy and paste text from
http://www.crutchfield.com/App/Product/ ... ailed_info
Wiring Note
Power Wiring: If the unit is connected with an IP-Bus cable, it is not necessary to connect the red (+12 volts switched) power lead. The receiver may not work properly if the IP-Bus cable and the red power lead are used together. The Installation Manual incorrectly states that both leads should be connected. A manual correction sheet is provided
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Looks like the power does not have to be connected when IP-Bus is being connected.
Did anybody installed the unit just with IP-Bus cable and no power cable connected?
Thanks.