Problem with one Polycom phone

Hi all, I’m running FreePBX FreePBX 14.0.13.4 with Endpoint Manager. All modules are up to date.
Today we had an issue with one of our phones (Polycom VVX 400, which was originally set up using the Endpoint Manager). This phone has been working successfully for many months; almost a year since I set it up. Today it started ringing, and the caller ID is 12345. I factory reset it, and after the factory reset, it still rings immediately upon bootup, and the caller ID is still 12345. I tried a new cable, plugging into a separate port on our PoE switch, and same behavior.
I made sure the firmware is up to date (version 6.1), but no luck.
Now it’s constantly ringing with a caller ID of “100”.
I think this is a problem with the phone, but does anyone have any ideas why this glitch would happen?

I’m not sure how this fixed the problem, but I did the following:

  1. Plug the phone into a wall power supply, disconnect the Ethernet port so it is powered from the wall power supply, not PoE, and has no network connectivity.
  2. Factory reset.
  3. Plug the phone into Ethernet, and re-input the provisioning server.
  4. Success! No more ringing!
    I suspect some file got corrupted somewhere, but I’ve never had this issue before.

This stinks of SIP ALG and ghost calls. My default ghost calls spiel:
These calls are sent directly to your network’s IP address, from automated scanning tools, by hackers looking for PBX systems to break into. They do not pass through your ITSP equipment at all. This is a common problem when using home or consumer routers with VoIP (Voice over IP).

In an effort to ‘help’ IP phones, consumer routers will keep the default port for SIP traffic (port 5060) listening on the router for connection attempts. This is fine until your IP is scanned and results in ‘ghost calls’. You can sometimes speak to the manufacturer of your router or modem about disabling this help, sometimes called ‘SIP ALG’, to keep this from happening. Another option is to only allow incoming connections to port 5060 from your ITSP.

Compiled list of routers that we know have this issue. You can review this list here:

https://virtualtone.com/routers-blacklist.html

Another possibility is that “something” was causing the phone to pull more power than your POE could provide. When the voltage dropped, the phone tried to keep going, but couldn’t. Using the wall wart powered it up until you could get it reset.

Thank you all for the suggestions. As far as networking, I use a Cisco RV325 router, with the latest firmware. It is EOL, but still does the job until we get a few nickels together for a new unit. I have SIP ALG turned off on the router, as calls weren’t getting through with it on.

Dave’s suggestion is also interesting. Behind the RV325, I have a really old Cisco Catalyst 3750 PoE switch, that is really only there to provide PoE. This particular phone with the problem does have a sidecar expansion module, but I found the Catalyst didn’t provide enough power. So I bought a wall wart PoE+ power supply, and powered it that way.

I’m going to push my folks for a new router, as ours is EOL, but in the meantime I’ll continue to monitor and only allow incoming connections to port 5060 from our (remote) phone server.

This topic was automatically closed 7 days after the last reply. New replies are no longer allowed.