We have a Viking Emergency call station that is setup with SIP as it is IP based.

The unit is able to make calls to my extension but when you try and call it, my Toshiba phone shows "Extension Vacant"

The Viking unit shows as registered to the SIP server and the Toshiba show on the MIPU16 that it is idle and show IP address.

Viking says it is the Codec that Toshiba is using.

I have it set to G711 on the CIX and G711u on the Viking device.

Has anyone else ever experienced this?

Thanks.

Can the Viking capture packets? I don't have experience with Viking tech support, so I don't know if the 1st guy started to drive into the PCAP.

G.711U or G.729 is what Toshiba uses. I would make sure that all other SIP Codecs are disabled. It doesn't really make sense to me that the Viking unit is not accepting the call based on the Codec if it is able to make an outgoing call, but strange things happen with SIP sometimes.