Somebody has a Thread on here where they were having a similar problem?
Seems to me like they took it apart to analyze the individual parts and found the latches had a taper worn on them.
Sasquatch has an excellent YOUTUBE Video on the disassembly and repair of this part.
You may want to check it out.
Those are great videos. Thanks for sharing. I've watched the last video before about bevelingbthe clutch discs. I did when I had the pony off and it works really well. Only problem while waiting on new nut locks to come in I got impatient and put the pony back on first. Oops!!