[G36_Me]

Glock lists the following probable causes for Failure to Eject or Erratic Ejection (including stove pipes)
Broken or damaged ejector - replace trigger mechanism housing with ejector
Underpowered ammunition - change ammo (your WWB should work, in my opinion)
Dirty chamber - clean chamber
Shooting with an unlocked wrist - lock shooting hand wrist
Lack of lubrication - lubricate (don't listen to folks who say no lube is required, follow the owner's manual suggestions)
Dirty gun - Clean

do note this: the ejector is actually a part of the trigger mechanism and a key to ejecting success. Of course, the extractor is important and needs to be checked, but also remember the ejector plays an important role.

good luck and keep us posted.