Troubleshooting voice call issues with the Grandstream UCM 6xxx devices

TopView can make VOIP calls for notifications through the Grandstream in order to call through an analog line.

This article provides a number of methods to verify your system is able to make voice calls through this device.

If you have not yet successfully made a test call through the Grandstream with TopView,

please ensure that your settings match those given in the set up instructions: ConfigureUCM6202forTopView.pdf (exele.com).

If you have made successful calls through the Grandstream in the past and did not receive an expected call, please verify alarms are occurring and TopView is attempting the call. You can verify behavior in TopView Admin Tools via the Alarm Actions Logs.

1. Run TopView Admin Tools
   
2. Make sure your Engine is selected at the top dropdown
   
3. Left menu: Alarm logs
   
4. Select an alarm event
   
5. Click the [View selected alarm actions...] button

If calls are not successful, the issue is usually with the analog line or the callee's phone line is busy.

If the phone is busy, another attempt will often work.

New SIP password requirements may result in Unauthorized and MaxRegAttemptsReached errors

Newer firmware released in 2026 changed the minimum SIP extension password length to 10 characters.
At this time the Grandstream configuration documents from Exele instruct the user to perform a batch creation of extensions with a SIP password of 9 characters. Although the batch extension creation is successful, users are unable to use these extensions until the password is increased to 10 characters. 

Test call logs will include the message Unauthorized and error MaxRegAttemptsReached.

Existing extensions with SIP passwords less than 10 characters will still work after the firmware upgrade.

Verifying line status

Log into the Grandstream via a browser. 
Left menu: System status > Dashboard

Each analog trunk should be blue if the line is not in use. If the trunk is not blue you should verify that the analog line is healthy

If the trunk is healthy, you have the following options:

1. Test calls in TopView Configurator in the Voice Notification settings dialog
   
2. Test calls through a soft-phone or hard phone as a Grandstream extension:
1. Details for both methods are in the set up guide: Grandstream configuration guide
3. Use the web admin portal's "Signaling Troubleshooting" guide (see below for more information)
4. Connect a phone directly to the analog line and attempt a call

Signaling Troubleshooting

The Grandstream's web admin portal provides means to make a test call:

1. Navigate to "Maintenance" > "Signaling Troubleshooting" > "Key dial-up FXO".
   
2. Type in the phone number where you'd like to place a test call, make sure to use a number that will work with the pattern set up in Outbound Routes.
   
1. e.g. if your Outbound Route expects a "5" to dial an outside line, make sure to include the "5" in your test number
   
3. Click the "Start" button to start the test call.
   

The device will attempt to make a phone call. Give this call at least 30 seconds to see if it rings your phone. After a minute, if you haven't been able to pick up the call and hear the audio playing, you can stop the test.

The logs include audio information, you can process this information according to the instructions provided in https://documentation.grandstream.com/knowledge-base/manage-analog-lines/.

If you cannot obtain Audacity, you can send the logs to support@exele.com for analysis. Please include the customer's name.

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