[Frobius]

You've got two options in the KOMBI module.

BC_DIGITAL_V_KORREKTUR - which obviously corrects the digital readout, and

BC_V_KORREKTUR - for the speedo.

That said, I've not actually tried it. I like the over read as default with the option of looking at the real speed on the digital display. It's bloody accurate too, always bang on with my TomTom.