Thanks for taking the time to read this. I'll get to it: I am using a UM-2G w/ advanced driver switch ON to send MIDI (on port 1) to and from an FCB1010 (midi foot controller). On my mac, I use a program called iFCB to edit the controller's presets; its SysEx dump function (which sends my edits to the controller) requires turning the device off and back on again (in upload mode). The problem is that my data always ends up corrupted, and here's why: The UM-2G is always outputting a signal (active sense?) – my foot controller detects this by flashing a light on its display. It is a known problem with the controller that if it is receiving ANY data upon start-up it will scramble its data. So my question: is there a way (with a driver? some other setting?) to DISABLE this signal that the UM-2G is constantly outputting? Again, it is a signal that is sent whether an actual MIDI message is being sent or not. Otherwise I have to use another, lesser midi-interface to make edits to the board, and it's becoming a huge pain to keep switching them out. Thanks for your advice, .A