I am setting up a FreePBX system for a very specialized application. To make things as efficient as possible, I removed all unneeded Modules from the system. One of those was Music on Hold.
When I attempted to add an Inbound Route, I got the error, "SQLSTATE: Integrity constraint violation: 1048 Column 'mohclass' cannot be null"
After re-installing the Music on Hold Module, the Music on Hold field appeared on the Add Inbound Route page and I can add Inbound Routes without an error.
I'm not sure if the Music on Hold Module should be required or if the mohclass should have a default value when not set/module not present. After installing the module, It appears that Module Admin will not allow me to remove it, but fwconsole ma will, so the way that Module Admin and fwconsole ma determine if a module is required or not seems to be different and inconsistent, which is how I ended up with Music on Hold removed in the first place.