That depends on which unit you are talking about, the software version in it and – more importantly – which View you are using and whether you are using the GOTO function or not. You can go into the Select readouts menu and set that digital readout location to display something else (or nothing). If it is not showing as being selected in the Select Readouts menu, than it is being displayed by default according to the View you are using and if you are using the GOTO function (travelling to a waypoint). If this is the case than it could only be changed by a change to the unit’s software.