How to eliminate ViciDial false positives and dead air
Stock ViciDial AMD misidentifies live callers as voicemail, but upgrading your detection stack stops ghost calls and recovers lost connections.
A step-by-step guide to fixing ViciDial false positives, catching carrier false-answers, and cutting dead air.
Predictive dialers depend on speed. When an outbound call connects, the dialer must decide instantly whether an agent should take the call or if the system should drop a voicemail. Legacy dialers rely on basic Asterisk applications like app_amd. These tools open an audio analysis window only after a carrier passes an answer signal.
The standard process is crude. The system measures silence lengths and noise bursts. If a prospect answers with a long greeting, background static, or a ragged response, stock silence detection panics. Asterisk classifies the audio into three rigid buckets: HUMAN, MACHINE, or NOTSURE. When it guesses wrong, it tags a live person as a machine and drops the call.
This failure pattern creates ghost calls. The prospect says hello, hears immediate silence, and hangs up. Beyond losing the lead, your phone numbers accumulate spam reports. Platform data shows that legacy ViciDial AMD misses the mark regularly, throwing away an estimated 10% to 20% of live customer connections before an agent ever hears a voice.
An overlapping issue that degrades call center efficiency is False Answer Supervision, commonly called FAS. FAS occurs inside the carrier path. An intermediate wholesale carrier sends a SIP 200 OK signal back to your dialer before the destination phone actually rings or answers.
To your dialer software, the SIP 200 OK looks like a successful connection. The dialer starts its internal call timers, begins billing, and fires off the default AMD evaluation loop. Because no human has actually picked up, the system listens to carrier-generated dead air or artificial ringbacks.
Standard silence detectors treat this dead air as a non-response or a timed-out machine. The call is logged as connected, billed by the carrier, and then abandoned by the dialer. Flagging these false connections requires analyzing the incoming audio stream directly rather than trusting raw SIP signaling flags sent by wholesale carriers.
Before modifying call routing rules, evaluate your current dialer infrastructure. AMDY.IO supports native installations across common open-source telephony distributions, including ViciDial, GoAutoDial, Asterisk, FreePBX, Issabel, and 3CX. It also supports custom predictive or power dialers via a WebSocket API.
Because there are zero setup fees and accounts include 50,000 free detections upon signup, you can test the audio analysis on live outbound streams without committing capital upfront.
Ensure your server has administrative access and outbound network permissions to establish socket connections. If you use ViciDial or Asterisk, the setup replaces legacy dialplan hooks with a streamlined installer.
For ViciDial, GoAutoDial, and standard Asterisk boxes, deployment requires running a single installation command in the terminal. This installer hooks into the dialer's media handling pipeline without requiring manual compilation of Asterisk modules.
Run the native one-line installer script on your primary telephony node. The script attaches the external detection engine to your call routing path. If you operate on FreeSWITCH or a custom dialer framework, configure your media server to forward audio streams directly to the WebSocket API endpoint.
Once connected, the engine bypasses traditional silence counters. Instead of waiting for prolonged pauses or full sentence completions, the system evaluates audio fingerprints in real time. Detection begins in 1/8 of a second after audio arrives.
The engine categorizes the incoming media stream into clear acoustic signatures:
With stream-based audio fingerprinting active, monitor your dialer logs to verify routing shifts. Compare your historical dropped-call rates against your new connection metrics. Reaching a 99% accuracy rate eliminates the 10% to 20% false positive penalty native to legacy Asterisk setups.
By preventing ghost calls and dropping FAS connections at the audio level, agents spend their shift speaking to real people rather than waiting out dead air. The result is higher talk time, lower telecom waste, and protected caller ID reputation.
Stock ViciDial AMD misidentifies live callers as voicemail, but upgrading your detection stack stops ghost calls and recovers lost connections.
Legacy Asterisk AMD still drops live leads, but audio stream analysis and early FAS detection are reshaping outbound dialer architecture.
An engineering breakdown of stock Asterisk app_amd, carrier-level CPD, and real-time audio analysis engines.