First post on here and it’s a bit mundane (also I did search but not seen anything obvious on here). My OP-Z arrived yesterday and as soon as I took it out the box the yellow volume / power switch came off. Basically just slipped off as soon as I used it. It still works fine and wasn’t sure if this was a “feature” by design or if I needed to return it.
Thanks in advance for any advice
Certainly not a feature. Return it.
My second op-z (replacing one that started double-triggering) has the same issue but I kept it because it didn’t double trigger and felt materially more solid than the first. It falls out very rarely 
So, yeah maybe replace it if under warranty. TE should provide perfectly working units, but sadly QC is amiss 
I put just a little dab of high strength threadlocker on mine and it’s staying put. Used to fall out all the time. Similar low strength adhesive should work too.