When I got my own U1272A I did notice that at the back of it, the tilt bail lock mechanism,
was a bit off position.
This caused the tilt bail to open by it self.
I did notify Agilent about it, but I could not wait for their fix,
and so I waked up the Odysseus from Ithaca that I hide in me..
I was trying for hours to find one simple and easy solution,
that every one can reproduce, even an 10 years old child.
And I did find the solution.
All that I had to do, was to add one tiny bold-nut 2.2mm thickness at top point,
of the locking system.
To enter the lock nut in there was almost easy to do.
And when it was in place, I just use my hot air gun, for 10 seconds,
by aiming on the tiny bold-nut.
The lock point moved down just 0.5mm, and that's it.
I waited 30 seconds so the plastic to cool down with the bold-nut in place.
If the center point goes is place with the heat, the bold-nut starts to free-play,
and the removal of it needs no effort.
Three minutes later = complete cool down, tested it and I got 100% success.
And the most amazing, is that the lock mechanism is very well made,
the locking point on the tilt bail, is made in a way that the middle axle acts as spring,
and in long term, is almost impossible to be ever an issue in this area.
Check the pictures !!
If you got unlucky by having this issue on your DMM, just follow my steps !!