Intercom Does Not Activate Relay Using DTMF from Cisco/Linksys SPA Series Phones

Intercom Does Not Activate Relay Using DTMF from Cisco/Linksys SPA Series Phones

I am using Cisco/Linksys SPA series deskphones.  The CyberData intercom does not recognize the DTMF tones from these phones to unlock the door.  

CyberData devices may detect more than one digit press when the ‘Mark All AVT Packets’ is set to Yes on Cisco/Linksys SPA series phones.  This can result in a relay activation code failure because the detected code does not match the configured code.

To resolve this issue, set ‘Mark All AVT Packets’ to No on the Cisco/Linksys SPA series phone. 

Attached are sample configuration screenshots of Cisco/Linksys SPA942 and 504G model phones where the feature ‘Mark All AVT Packets’ has been set to No.