Yealink T22 CTI Mode fails after v15 upgrade

[jms]

I'm getting multiple reports from the branches I have upgraded to v15 that several times a day the softphone client loses connection to the deskphone.

A user will pick a number or manually enter one, press Enter or click Call, and nothing happens.

If the user pulls the POE cable and re-boots the deskphone, it works until next time.

Also, if I re-boot the handset from the server management interface, it works until next time.

I have tried uninstalling and reinstalling the client but it seems to make no difference.

The deskphones are Yealink T22s. I updated firmware to latest with the v15 release.

 

[jms]

I have just found out that when this happens, the deskphones are on the network and can be pinged and indeed reset by the web management tool, but I cannot connect to the phone's web interface on port 80.

 

[jms]

I'm thinking it has to be the 3CX server doing this.

Two of the deskphones are not connected to a 3CX softphone Windows client. I re-start all phones from the 3CX management interface, and confirm I can get to their individual web servers.

When I get a call from a user saying their softphone will not drive the Yealink T22P in CTI mode, I try to get to the web servers on the deskphones, and Chrome reports ERR_EMPTY_RESPONSE from all, including the ones not being used by 3CX softphone Windows client.

Those two phones don't even make calls. One is in a spare office and one is in a meeting room. Their web server locks up at about the same time all the other ones do. The only things that have changed are firmware has gone from .54 to .60 and 3CX has gone from v14 to v15.

 

[jms]

My branches are all connected to Sydney head office, where I am, by a WAN. I have one extension in Sydney which is connected to the Brisbane 3CX server. When the web server on all the Brisbane handsets stop responding, the Sydney handset continues to work okay. The Brisbane network is 10.40.0.0/22. The Sydney network is 10.20.0.0/22.

My firewall allows all traffic between local and WAN addresses except broadcasts of course, so it may be broadcast traffic of some sort that is causing this.

 

[jms]

I uninstalled v15 and reinstalled v14sp3 in my smallest branch early this morning. I left the v15 softphones on the workstations. They seem to work with v14 except the envelope icon doesn't go blue when you get a voicemail.

The problem hasn't recurred in that branch today. It still exists in the other three branches I upgraded.

All the Yealink T22s in the Auckland branch had frozen webservers at 14:10 today. I re-started half of them at 14:10, and the other half at 14:50.

I refreshed their logon pages in a browser every ten minutes or so. I wanted to see if they froze at the same time or a certain number of minutes after the last restart.

At 16:00 all of the web servers were frozen.

 

[jms]

When I rolled my smallest branch back from v15 to v14, v14 downgraded the firmware in the Yealink T22 handsets.

I manually upgraded the firmware on two deskphones from 7.73.0.54 to 7.73.0.60 in the v14 branch on Friday evening.

On Saturday evening those two deskphones had frozen web servers. Web servers on all the other handsets were working.

I went to one of the branches that I had upgraded to v15 and downgraded all the deskphone firmware to 7.73.0.54.

I will check results in a day or so.

 

[jms]

Monday morning, and none of the phones which I downgraded to firmware 7.73.0.54 have frozen web servers.

The workaround is:

If you upgrade to v15, don't click the Updates link in Dashboard and get the new firmware.

If you've already done that, rename C:\ProgramData\3CX\Instance1\Data\Http\Interface\provisioning\bpgx04vxfu\firmware\yealink\T22-7.73.0.60.rom and C:\ProgramData\3CX\Instance1\Data\Http\Interface\provisioning\bpgx04vxfu\firmware_new\yealink\T22-7.73.0.60.rom. Get T22-7.73.0.54 from one of your old backup zips or the Yealink web site, log in to each phone's web server, go to Settings, Upgrade; browse to the .54 file and click Upgrade.

 

[jms]

I lodged a support ticket with Yealink as follows:

"The internal web server on the Yealink T22 hangs when firmware 7.73.0.60 is installed. When this happens 3CX cannot make CTI connections to the phone. It does this with 3CX v14 and v15.

Everything works fine with firmware 7.73.0.54, with 3CX v14 and v15."

Their answer was:

"Great to hear that, please use the 7.73.0.54.

I guess it's compatible problem."

I guess it is.

7.73.0.60 doesn't seem to be available for download on the Yealink web site any more. 3CX still lists it as an option when I click Updates from the dashboard and select Phone Firmware.

If I click the Phones link at left, I get a listing of my Yealink SIP-22Ps, showing the Fw. Version as "Not Supported 7.73.0.54".

 

[jms]

v15 prompts me to install bad firmware which locks up my Yealink T22P phones. If I ignore the prompts the management console lists my phones in red with "Not Supported 7.73.0.54" next to them.

I've paused my v15 rollout because of this issue. About 70% of my users are still on v14.

The comment beside the bad firmware update in v15 is "Yealink T22P FW: Added support for Lets Encrypt". How important is this if I don't need secure SIP? Will v15 and future versions work with the 7.73.0.54 firmware?

Can I stop the phones with working firmware from being listed in red? I'm concerned that one of the other admins will decide to make the nasty red lettering go away and update them all to the bad firmware.

 

[NickD_3CX]

As far as I am aware, specifically for the T22 should also be OK with 7.73.0.54 firmware for now, however I cannot say what the future holds.

We are currently investigating this issue, when I have an update I will try and update this post.