Configure Polycom VVX 400 for JustCall

Set up my phone system2 min readUpdated 2026-03-14

Configure Polycom VVX 400 for JustCall

Connect your Polycom VVX 400 desk phone to JustCall using SIP credentials.

Available on: All plans


Step 1 — Find your phone's IP address

On the phone, go to Home > Settings > Status > Platform > Phone. Note the IP address.


Step 2 — Access the web interface

  1. Open a browser and go to http://<phone-IP-address>/.
  2. Log in with username admin and password 456.
  3. Go to Settings > SIP > Line X.

Step 3 — Configure SIP settings

SettingValue
SIP URIusername@justcallv1.sip.us1.twilio.com (replace username with your JustCall SIP Username)
Domainjustcallv1.sip.us1.twilio.com
Server 1 Addressjustcallv1.sip.us1.twilio.com
Server 1 Port5060 (or 5061 for TLS)
Server 1 Expire3600
Server 1 RegisterYes
NAT Keep-Alive20 seconds
Auth User IDYour JustCall SIP Username
Auth PasswordYour JustCall SIP Password

Verify connection

A green indicator means the connection is successful. A red indicator means credentials may be incorrect — check Diagnostics > View Logs for details.


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