If you have the empeg plugged into the dock, and are powering it off of the AC adapter, it may be in AC mode and not think you have a tuner attached.

This is incorrect.

Whether or not the player uses the attached tuner module is completely independent of the AC/DC operating mode. The tuner works fine in either mode, and you do not have to do anything special to make the player recognize it when it's in AC mode. Simply attach the tuner to your indoor docking station and it will work.

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