Failing Keyboard?

[David Berg <drberg1000@gmail.com>]

If xev doesn't report a certain keyboard event (Left shift or ctrl
plus [d,c,e,3,t,b]) does that pretty much indicate the keyboard is
failing?  I checked to see if the plug was fully seated, and it wasn't
quite all the way in, though I think the connections were solid.  Is
there a way to make sure without rebooting?  Are there config files
that might control this?

To me the odd thing is [shift]+Q and many other characters work fine
but dce3tb and possibly others do not. And occasionally [shift]+d
works.  It seems somewhat time based.

I appreciate any help.  

Dave