A system and method is described that allows a system operator to remotely detect and diagnose a voice-enabled cable modem that has entered a chattering line state so that appropriate steps may be taken to avoid or rectify any of the problems that may result from this condition. Logic within the voice-enabled cable modem monitors for pulse dialing activity and/or excessive hook state and/or flash events that may be attributed to a faulty telephone and/or telephone line connected to the voice-enabled cable modem. Responsive to detecting such conditions, the logic within the voice-enabled cable modem reports a fault condition to an external management system via a cable data network.