Ok is anyone else seeing their third weapon set (opened with arms bearer) unequipping itself? Perhaps on level ups but I never notice it until I look up and Eder or someone is boxing instead swinging their weapon. (I tried a couple half-hearted searches to no avail )

 

Yeah if I put them back five mins later there not there again.

This is a confirmed bug, it happens on level up. Not sure if it's fixed yet in the patch, but they're aware of it.

Noticed it too. If I had to speculate, it might be that the game wipes your character, then remakes it at level up, which results in the item sets temporarily disappearing?