We are using Cisco Spark with Hybrid & Call Connect etc. When calling an external number all is well, it sets the caller ID number to the one we set as "External Phone Number Mask" against the users Spark CTI device line. However, when calling an internal number, like VoiceMail (goes to Unity), it's also sending the external mask as the caller ID, so when it reaches Unity the extension is not recognised and it doesn't take the user straight in to their mailbox.
Has anyone see this or know what the cause may be?
Thanks
James