The GBFans Sound Board is usually set to “Test” mode when you unbox, so if you review the manual .pdf and double check your dip switches to make sure they aren’t ALL turned to the off position (The sound card’s “test” mode.) you should start to hear some noises from your setup!
DIP Switches = Dual In-line Package. The black rectangle with the tiny white squares on the board. They slide back and forth to be either closed or open. The positions tell the micro controller how to behave. GB1 sounds only? GB video game sounds? Test only mode?