u/Glum_Load_7271

Hello folks,

I bought this three row 31-Button 12-Bass Hohner from ebay and it has ... almost ... this layout. There a button with double-c on the F-Row and a double-g on the C-Row and I wonder if this an intentional customization or a well known exception and a strategy behind it. As a new player it seems weird to me to pick the missing d and a from the neighborhood. Does anybody know what's behind that?