I am not sure this is resolved...but...my first thought was that something might have worked loose. I checked everything, or so I thought, and did not find anything that was noticably loose. I did tighten the bolts that hold the sides of the case but these are not structural. They were, however, very loose and it did seem to help a little? Could just have been me.
In any case my post on the Reprap Forum confirmed my original suspicion that it is probably something loose so I checked again. This time I remembered to check the two bolts that hold on the extruder assembly and sure enough they were a little loose. I do mean a little but every little can count. So I tightened them.
In order to check these bolts I had to take off the directed cooling duct that I have installed. This duct not only blocks those bolts but it makes it challenging to see the nozzles. Once it was off I was able to notice that the nozzle that I have been using was in bad shape with caked on plastic. So I cleaned it.
I have done a couple small test prints and I think it might be ok now. In a few minutes I will do the real thing.