Input ports selecting for Retrospecting Record


I made simple example, this topic more about midi splitting to different ports.

If I play on instrument with several midi-ports, transmits simultaneously, double notes occures.
As I understand, problem in recording all incoming signals from any ports to current selected track. For fix it additional option in Cubase preferences needed - selection of input midi port for Retrospective Record, as one of option - to record only from port, connected to selected track.