HUUUUURRRRRRRRRRRRAAAAAAAAAAAAAAYYYYYYYYYYYYYYY I FIGURED IT OUT.
I had the same problem for a week straight even went and purchase another CD-IB100II believing the first was defective. Granted that you are connected to the 12 v battery constant Ground, ground and ground and only to bare metal. Any metal covered in paint or anything will not be proper ground. THANKS GOODNESS FOR THE VOLTMETER I WAS ABLE TO VERIFY THE VOLTAGE GOING TO THE CD-IB100II. As the book state 14.4 volts. If not ground properly the device will not have enough power for ipod, iphone, etc
PS
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