I found a thread about this, and found the remnants of a piece of foam on the arm that pushes the tonearm peg back to rest - now reduced to a light film of pinkish-colored goo. I neglected to photograph the "before" image, but here's how to fix this:
I had the bottom off, and the TT set up between the bench and a chair w/woodblock so I could have it operate
and watch it.
Start the unit, so the automatic mechanism is at 1/2 revolution (if you want easier access from the Rt side as I did), then unplug. In the photo below you can see the little arm in question, and the new piece of (blue) foam:
With the TT "on" (unplugged) you can easily flip the arm to the left, which made it easier to clean - I used laquer thinner and a Q-tip to remove the sticky mess. The foam, I found at a surplus store. It measures exactly 0.25". Here's the arm flipped w/new foam:
***Don't forget to flip the arm back where it was before restoring power, otherwise it will jam - easy to fix, but easier to avoid***
and here's the extra piece - I couldn't resist a small glimpse of my new precision machine:
Hope this helps, it worked wonders for me!
Cheers, Gavin