Initially when calling voicemail boxes or main greeting callers got silence. Had customer reboot then audio came back but now callers cannot leave a message
they get a recording "Recordings cannot be made at this time try again later".

Activity log shows: "Unable to create record file" and "unrecoverable error" and "VMT at sayndx sfname open error"

Thanks in advance.

My guess is a bad sd card.

Had same thing happen and yes it was the SD Card that would not write..

Thanks. That was it.