Unstable Phone Connection

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Asterisk Users 2 Comments

This is driving me to distraction. I have a switch with multiple clients who are all working fine except for one and I can’t figure out what makes them different. I have tried every NAT setting in the ATA
(SPA112 ATA with 2 x FXS, 1 x LAN), stun server on and off, different sip ports, different RTP ports and it still fails. I have left the location with it working only to have it fail later. He always gets registered but when a call is sent it doesn’t respond so the caller hears no ring and the phone does not ring.

Yesterday he mentioned that when the phone is working the WiFi slows down significantly. No idea why or if it is related.

He has a radio station streaming music. I wondered if that might be interfering. That’s why I tried changing the SIP port and the RTP
ports but that didn’t seem to help.

It smells like a network problem to me but I am running the same ADSL
device here and other clients are working behind a NAT gateway so I am at a loss as to what might be wrong. Could it be the streaming?


2 thoughts on - Unstable Phone Connection

  • D’Arcy J.M. Cain

    If the device is registering and then dropping there are several usual items.
    The router may be closing the ports on the device. The router may have a AGL SIP helper that is causing issues.

    Make sure that the device is sending out keep alive packets. Shut down any AGL helpers on the router. Make sure that the site is not double NATing

    Try using a stun server and see if that helps at all. Watch you console on your sip serer to see how long the device runs before losing connection.


    Bryant Zimmerman (ZK Tech Inc.)
    616-855-1030 Ext. 2003


  • I don’t see how. I am logged into the ATA through the router and I
    don’t lose the connection.

    Can’t find an AGL setting. There is a SIP checkbox. Pretty sure I
    have that turned off but I can try to get someone to check.

    I have that flag turned on.

    See above.

    There’s only one router. It is the ADSL device as well.

    I tried with and without. I am using stunserver.org.

    I don’t think it does. Both the server and the ATA think that they are still registered but when a call comes in there is no ringing on the line. If I split dial it rings the cell phone but I still hear no ringing from the caller side unless registration is actually turned off from the ATA and a “sip unregister” is issued.