Keyspan 1.9 - Manual (Page 23)

port on your computer. If this solves the problem, then this may be an issue with your USB hub. If
you are encountering this problem or something similar to it, please contact
Keyspan Tech Support
for further instructions.
Keyspan:High Speed USB Serial Adapter for Mac OS-v1.9 User Manual
This User Manual applies to the Keyspan High Speed USB Serial Adapter Software for Mac OS.
(rev 02may12JA)
Page 23