I'm stumped.  I bought it, and experienced this first thing.  So I tried connecting it to a different PC--same outcome.  So I ordered a replacement--same outcome.   So apparently I'm doing something wrong as I don't find comment about this anywhere in my web search.  I chose not to install the Smart Technology software (I think it's called) as I've seen some comments that no drivers are required.  And indeed-it works perfectly...as long as I pull the USB connector out, and put it back in.  Doesn't matter which of the 3 different USB ports I've tried this in either.  FWIW, I have FSUIPC installed, and have had the boxes relating to disconnecting the elevator trim when the A/P is on both checked and unchecked but to no avail.

 

Thoughts?  Thanks in advance--I really like this thing but don't know how to keep it connected!!  

^{Bump, same here}