MIDI event question

I am triggering HOG4PC cues via MIDI notes, inputting them to the computer via an M-Audio Uno input device. Everything is working fine, however the MIDI viewer shows a continuously repeating event:
"Could not get Midi Out device 1 capabilities so skipping.."
This event repeats forever. If I unplug the M-Audio Uno, it stops. When I plug the UNO back in it starts up again, but it now reads:
"Could not get Midi Out device 2 capabilities so skipping.."
This repeats indefinitely as well.
This does not appear to effect the operation of the cues at all, but I am not comfortable leaving this event without knowing if it could have a detrimental effect on the show over time.
Does anyone know anything about this? Is this something that I can make stop? Or do I have to even worry about stopping it?

Thanks!