USB-UIRT stops being able to change channels SageTV Win 7 64

I am using Sage TV (latest 6.6) and the USB-UIRT stops being able to change channels all the time. I have to unplug the USB-UIRT from the USB Port (it is plugged into the back of the PC USB Port) to get it to
work again.
I have Windows 7 64 bit with all updates applied, Sage TV 6.6 latest and USB-UIRT with latest driver from USB-UIRT Web site ver 2.0.2.16 (dev mgr shows FTDI, 2/17/09, ver 2.4.16.0).
This is very frustrating. I saw some posts on the topic but not solutions.
Can anyone explain why this is happening and if there is a fix?
Thanks
work again.
I have Windows 7 64 bit with all updates applied, Sage TV 6.6 latest and USB-UIRT with latest driver from USB-UIRT Web site ver 2.0.2.16 (dev mgr shows FTDI, 2/17/09, ver 2.4.16.0).
This is very frustrating. I saw some posts on the topic but not solutions.
Can anyone explain why this is happening and if there is a fix?
Thanks