Ok, I think I have narrowed mine down to a clash with the plugin Types – Complete Solution for Custom Fields and Types by ICanLocalize
When adding a new event, or editing an existing event none of the Event custom fields are saved. Deactivate Types and it works as expected. I have not tested whether Types is functioning normally with Events Calendar installed. Although I cannot be sure I think this only occurred after the recent update to Types.
I have set up a test site which I have stripped down to the two offending plugins.
This is at testing.oandb.info
A login with admin rights is ‘test account’
password ‘clashreport’
I have reported this to Types developers too. I wonder what you think?