Broke mine a few months ago also, my fault though
. It came forwards and i think i bumped it with my arm turning round to grab belt or something, but hasn't worked right since, goes in and out no bother, but chrome part on end doesn't retract properly on way back in. Removed arm to find small plastic pin halfway down snapped off inside rear panel, £216 all in from local STEALERS
, No way I'm paying that for a 12" plastic arm, I'll keep hunting ebay and breakers or try making the small part @ work.
Davie