Settings/sip cancel reasons to ignore missed call/VALIDVALUE
From Snom User Wiki
- Space separated list of reasons. Each reason starts with either text=, cause= or cause< followed by the value that would be in the sip-cancel-message. If the text-reason-value contains spaces, it must be quoted (see default value as example).
- There is one proprietary text-reason-value which we use when an incoming call changes it's caller via re-invite with replaces header:
- ->text='Call was replaced'