Message: The port “Avid DNA” is busy and cannot be used for deck control.

[Vito Defilippo]

This has happened to me before, and it always turns out that I have an extra channel that has somehow appeared in my deck configuration. Open “Deck Configuration” in your settings list. Usually I have just a firewire channel, with an associated deck (I’m using just the software version, nothing other than firewire for connecting decks). If you have a second empty firewire channel there, try deleting it.