I just got my DWA-160 Rev. A and installed it with the included CD.  Everything worked fine and I have a 300 Mbps connection with my DIR-655 Router.  I thought I should upgrade to the latest driver so I downloaded the 140 and loaded it.  I had to remove my old driver and unplug the adapter to get it to load.  After loading I can see my network but it fails to connect after I enter the security phrase.  I then removed the new driver and re-installed from the CD and everything works again.