Are you dealing with a factory stereo or an aftermarket unit?
Ok, what brand and model number is XXXXX?
Press and hold the rotary encoder for more than 3 seconds to
access the setup menu. Press the rotary encoder momentarily
encoder left/right to adjust or activate the desired function.
LOC OFF Activates distance tuning.
LOC ON Activates local tuning for strong station reception
Have you tried the tuner in both modes?
In all probability you have a bad unit. I would recommend calling Dual directly at 1-866-382-5476