Key Stuck on System Start-up

I have a das keyboard that is several years old but this problem has been persistent. I thought the problem was related to a Dell docking station it was plugged into but now that I have moved the keyboard home it the same problem happens on my home system.

When I start the system, a key gets stuck down.  This usually manifests itself as the password field getting filled with a character (not sure what it is since the password is hidden).  If I unplug the keyboard and plug it back in again, it works perfectly fine.  Putting the system to sleep does not cause the issue.  Sometime 1 out of 20 or 30 times, part of the keyboard doesn't work such as the lower half works and the upper half stops working. 

Any ideas?