Yealink SIP-T27P not supported

[datalit]

Hello,
after updating to version 18.0 Update 3 (Build 461), we see the Yealink SIP-T27P phones listed as not supported and we have problems because there are intervals of a few seconds in which it is not heard, the phones are on version 45.82.0.20 and on the Yealink website the latest is the 45.82.0.30 but on another site we have same phones with version 45.83.0.130 (?).
Can this problem be related to the version of the phones and can it be solved?
Thank you

 

[Saqqara]

Yealink T27P are supported as legacy devices - https://www.3cx.com/sip-phones/yealink-t20p-t22p-t26p-t28p/. You have to scroll thru the list of phones, and you will see T27P

3CX supported firmware is 45.83.0.130 - https://www.3cx.com/support/phone-firmwares/

Please provide info on your setup - https://www.3cx.com/community/threads/information-to-provide-when-requesting-help.67558/

 

[JohnS_3CX]

Hello,

Please follow our guide here when setting up your phones. There are links included which help you install the latest version 45.83.0.130 supported by 3CX. https://www.3cx.com/sip-phones/yealink-t20p-t22p-t26p-t28p/

Alternatively, you can also use the Firmware button in your management console to try and update automatically.

When this is done, you can check to see if the problem is solved.


If not Solved:

Read the below article carefully, and provide us with further information so we can understand how the phones are deployed
https://www.3cx.com/community/threads/information-to-provide-when-requesting-help.67558/

 

[datalit]

here is more information

• 3CX Version, 18.0 Update 3 (Build 461) in both sites in which we have the problem
• Server OS, Windows 10 Professional (both)
• Is the 3CX Server Hosted and where? On-premises
• IP Phone Make/Model/Firmware version, e.g. Yealink SIP-T27P (versions 45.82.0.20 and 45.83.0.130) and SIP-T27G (69.82.0.20 and 69.83.0.35)
• Provisioning Method: Local
• Trunk Provider or VoIP Gateway Make/Model, CloudItalia (voip.eutelia.it)
• Has the Firewall Checker passed: YES
• Are custom Phone Templates being used: YES

all those phones are listed in red as not supported

 

[Saqqara]

Reason the phones are listed in red, you are using custom templates. You can ignore this message

I would upgrade the firmware on the devices to 3CX supported firmware - https://www.3cx.com/sip-phones/firmware-update-yealink/

 

[JohnS_3CX]

here is more information

• 3CX Version, 18.0 Update 3 (Build 461) in both sites in which we have the problem
• Server OS, Windows 10 Professional (both)
• Is the 3CX Server Hosted and where? On-premises
• IP Phone Make/Model/Firmware version, e.g. Yealink SIP-T27P (versions 45.82.0.20 and 45.83.0.130) and SIP-T27G (69.82.0.20 and 69.83.0.35)
• Provisioning Method: Local
• Trunk Provider or VoIP Gateway Make/Model, CloudItalia (voip.eutelia.it)
• Has the Firewall Checker passed: YES
• Are custom Phone Templates being used: YES

all those phones are listed in red as not supported

Firstly follow the instructions to install the correct firmware - then reset the phone and provision it using the default templates.

You should confirm that it works fine like this before you make any custom templates otherwise you won't know where to start from troubleshooting.

 

[datalit]

before the 3cx update, with the custom template, we didn't have the problem
now I noticed that the problem occurs also with the Windows App so I'd exclude the problem is phone's version related
maybe some settings were lost in the update? we already fixed some but maybe we missed others

 

[Saqqara]

Are you running anti-virus on the machine even MS defender, if so exclude the 3cx folders

• C:\Program Files\3CX Phone System\*
• C:\ProgramData\3CX\*

 

[JohnS_3CX]

there are intervals of a few seconds in which it is not heard

This description points towards network issues (especially so if VLANs, VPNs or various subnets are involved).

It is often noticed when some of the audio traffic is lost, or blocked by the network. Also you haven't mentioned whether this happens with trunk calls or internal calls or both.

before the 3cx update, with the custom template, we didn't have the problem

Not impossible, but doubtful. Otherwise we would very likely have had thousands of customers complaining about this and currently we do not have such feedback from our customers at large.

now I noticed that the problem occurs also with the Windows App

This now points more towards network issues. Since you are on Windows, now is a good time to point out that the machine needs to be dedicated to 3CX: it should just have Windows, Drivers and 3CX - nothing else. That includes antivirus packages that often mess with the the 3CX Services and also try to filter the NIC, causing trouble with traffic.

Once this is resolved and the apps work fine, you can resume dealing with the deskphones.

- For now try what @Saqqara said, or disable your antivirus entirely during testing.
- Let us know if only external calls are affected or internal or both.
- Confirm that the hardware you are using is sufficient for the latest version of 3CX from here
- Tells more about how your network is setup and if if VLANs, VPNs or various subnets are involved

 

[datalit]

I disabled the real time protection on the 3cx server
we don't call internally
hardware is above the requirements
we have different subnets for server, computers, and phones
I tried to change the codec without solving
from:
G729
G722
PCMU
PCMA
to:
G729
PCMU
PCMA
G722

in the control panel I noticed a firewall error and running the test I get:
testing 3CX PhoneSystem 01 SIP Server... failed
testing port 5060... full cone test failed
testing 3CX PhoneSystem Media Server... failed
testing ports [10600..10998]... failed
it seems the range of ports has extended now we change it on the firewall

 

[JohnS_3CX]

The ports have been 9000-10999 since at least version 15.5 you can see here which ports do what. For external calls you need the UDP range I mentioned, plus your 5060 port to be port forwarded correctly on your router and/or modem.
https://www.3cx.com/docs/ports/

Please take a look at this 3CX Academy training video / slides it will help you get a better idea of how to deal with the firewall settings until you can run the test successfully
https://www.3cx.com/3cxacademy/videos/basic/nat-port-forwarding/

Let us know if you have any questions after watching it

 

[datalit]

we modified the firewall accordingly and now the test passes but the problem persists

 

[JohnS_3CX]

At this stage, you need to replicate the issue while you run a capture. I still suspect network issues, but you have to start from somewhere, like the source of the missing audio which comes from your provider.

This capture can then be downloaded and sent to your provider CloudItalia with a description of the problem.

You said you noticed this also happens with Windows client and Yealink phones, and you only make external calls which must necessary pass via the sip trunk so I think this would be the next logical step.

 

[datalit]

would it be possible to downgrade to the previous version while we fix the problem and how?