Thunderbolt ethernet does not connect when plugged in.
I have a rMBP 2.3 gHZ, 8 gigs RAM running OS 10.8.1. I usually use wifi to connect to my network at work, but sometimes signal strength is low and I plug in my Thunderbolt to ethernet adaptor. The laptop does not recognize that I have plugged in, and to solve the problem, I have to open my network preferences and try to force it to connect. I shut down wifi, doing only this doesn't solve the problem; the machine still says that the ethernet cable is not connected. Then I go to the "advanced" window and click "renew DHCP lease." It doesn't connect right away, but when I close the advanced window, it will usually connect to the network. I have the impression that it doesn't work the same way every time, but I haven't been systematic enough yet to be sure. I have tried setting a specific location "work" for the ethernet connection so that I can select that state when I need to use ethernet. This did not solve the problem.
My adaptor is the genuine Apple unit, not an after market.
Any ideas? Any others have this issue? I'm hoping it's not a hardware problem.
MacBook Pro with Retina display, OS X Mountain Lion (10.8.1)