How to Solve the Unknown Calls Issue after Call Hang-up from PSTN line

Background: 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.

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.

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.


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