I have a regular 2d blue connection transducer connected to my unit as well as a 3 n 1. When I go to my sonar settings it shows Channel 1 off and Channel 2 on and the 3n1 listed as the source. When I turn on Channel 1 and go to setting it does not show both channels and it shows unknown as the source. Is there something else I need to do to show both channels as well as the transducers connected?

I am going to send you a PM to call me when you are in front of your units, but try INSTALLING the 2D ducer under - PAGES -- SETTINGS -- SONAR -- INSTALLATION and choosing your 2D transducer.