Unknown Calls Issue after Call Hang-up from PSTN line


In some counties, PSTN provider will send the message indicator signal after you hang up the call. This makes MyPBX identify it as a call. However it would show "Unknown" on your phone display.

Simple Resolution

Firstly and usually you can add a "X." in the Caller ID Number field of inbound route to eliminate the issue.

However if your line doesn't owns a caller ID service, this method doesn't make sense.

Better Resolution

Fortunately you can try to utilize the following guide to solve the issue.

Please follow the procedure to figure it out:

1. Verify if you have the get the similar log in the Asterisk CLI mode.

    -- Starting simple switch on 'DAHDI/1-1'

[2015-02-09 13:51:03] NOTICE[5597]: chan_dahdi.c:9966 ss_thread: CallerID number: (null), name: (null), flags=44

[2015-02-09 13:51:03] NOTICE[5597]: chan_dahdi.c:10145 ss_thread: MWI: Channel 1 no message waiting!

    -- Executing [s@DID_trunk_1:1] Macro("DAHDI/1-1", "incoming_1604and1605,1,s") in new stack

Follow this guide to enter the Asterisk CLI mode: Enter Asterisk CLI mode

Make a test call, answer it and then hang up. Wait for several seconds, when the unknown calls comes out.

Watch the log to check if you can see logs. "Flags=44" is the key mark.

If you can see the mark, you can go ahead.

2. Customize the users.conf 

1) Get a brief understanding about how to customize the configuration file in MyPBX with this link: User Defined Configuration Modification

2) Login the SSH and enter command mode by following Enter Command mode.

Input command: vi /persistent/custom-cfg/users_custom.conf.

3) Add the content like the following:


mwimonitor = rpas
mwimonitor = rpas


Note: "trunk_1" means pstn1, you can adjust the content according to how many lines you have.

4) Save this file users_custom.conf, reboot  MyPBX to make this modification take effect

4. Test the call again.


Have more questions? Submit a request


  • 0

    Hello everyone. I use S20 series and I don't find : /persistent/custom-cfg/users_custom.conf

    I need your help please....


Please sign in to leave a comment.