Duplicated events from spying MIDI driver

[krevis]

A user reports: after they've been using MIDI Monitor for a while, they're seeing events duplicated two or more times. These are events "to" a port, so they're coming from the spying MIDI driver.

Killing the MIDIServer appears to fix it.

(This is in events going to a BomeBox, when connected over ethernet. Might be peculiar to that device or its driver, somehow.)