Answering machine detection FAQ
Answers to the questions we hear most about answering machine detection (AMD), nomoVM, VICIdial integration, recordings and billing. This answering machine detection FAQ is kept up to date as the product changes.
What is answering machine detection (AMD)?
Answering machine detection is the step where an outbound dialer decides, in the first seconds after a call is answered, whether a live person or a machine picked up. Live people are connected to an agent; voicemail, carrier messages and fax tones are dropped or get a recorded message.
How accurate is nomoVM?
On 400 hand-labelled calls the model had never seen, nomoVM sent 94.9% of live people to agents, and 88% of the calls it sent to agents were people. The full numbers, including where it fails, are on the measured accuracy page.
How long does a verdict take?
About 2 seconds after answer for most calls. When the first 2 seconds are unclear (5 to 9% of calls), it listens up to 3.2 seconds before deciding.
What do AMDSTATUS and AMDCAUSE mean?
AMDSTATUS is HUMAN or MACHINE, the same variable VICIdial's VD_amd.agi already reads. AMDCAUSE says why: HUMAN, MACHINE, SCREENING, SILENCE, TONE, BUSY or UNKNOWN. AMDSTATUS is HUMAN only when AMDCAUSE is HUMAN.
What happens if the service is down or my key is wrong?
The client sets AMDSTATUS to FALLBACK before any audio is used, so your dialplan runs Asterisk's own AMD() for that call. No call is lost and fallback calls are never billed.
Which dialers does it work with?
VICIdial, GoAutoDial and any Asterisk 13+ dialplan through an EAGI script; FreeSWITCH through a Lua script and mod_audio_stream; anything else that can stream 8 kHz audio through the WebSocket API.
Does it work with my carrier?
Yes. nomoVM listens to the audio your Asterisk or FreeSWITCH server already has, so it works with any SIP trunk or carrier. Nothing about your routing changes.
Do you record calls?
Only the audio the model hears to decide: the first 2 to 3.2 seconds after answer. You can turn recording off, keep recordings from 1 to 90 days, and delete them at any time.
What counts as a billable call?
One verdict is one call. Fallback answers (wrong key, over the free limit, service unreachable) and health checks are never billed.
Can I resell nomoVM under my own brand?
Yes. The white-label plan runs the WebSocket and dashboard on your own domain with your logo and colors. See the white-label page or contact us.
Still have a question? Contact us, or read the API docs and the VICIdial AMD setup guide.
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