I was ok with the little rubber feet coming off, it didn’t affect the sound or the functionality or the look. But I’ve noticed a few buttons didn’t press right like the C#. And just now the sequencer button fell off completely and I can’t pop it back on
I am not knocking the build quality at all, I’m just sad if she’s going to start falling apart.
I recently came into the same issue (cursor key fell off). Provided the plastic isn’t broken check this link:
https://www.ifixit.com/Guide/OP-1+Key-button+Removal+and+Cleaning+Guide/20381
If that doesn’t work, email TE and they should be able to help.
Thanks for the link!