The older pio HU's had individual buttons 1-6. This way you could go to whichever radio station you wanted from 1-6 then again there were 3 modes FM1, FM2 and FM3.
The newer HU's don't have the buttons anymore. Now you have to press the up down button to go through the channels. If i want to go from channel 2 to channel 6 I have to press up button 4 times. Before it was just press the channel 1-6 button.
I like the older HU's better.
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