MOHClass issues on inbound calls

I noticed that Extensions can’t have a MOHClass set in the GUI, but I can import one via the Bulkhandler, if I set it there does it work though? I am trying to resolve a an issue w the wrong MOH playing on some calls after being routed in to the extension and being placed on hold, the inbound route was configured to provide the correct MOH (inbound route>announcement>ext)