Yealink: the handsets can hear the other conversations

[wouam31]

Hello everyone,


I am experiencing an issue with some Yealink DECT phones. The base station is a W70B and the (6) DECT handsets are W73H. All devices are up to date. All are on a single DECT base station.


My problem is the following: when I have multiple simultaneous calls on the DECT handsets, the handsets can hear the other conversations. This issue only occurs on the DECT handsets. I have T53W phones and I do not hear the conversations from these devices.


The registration is done via port 5061. I changed it to 5060 UDP by forcing yealink_sip_listen_port to 5060.


I also changed the default Yealink RTP ports on the base station to the FusionPBX RDP ports.


Nothing works.


I noticed that in the FusionPBX registration, the SIP accounts all use the same port. Is that the problem?


Has anyone encountered this issue before? Is there a way to register each account on a random and different port for each extension?


Thank you.

 

[glennbtn]

I am having the same issue with the W70B as our customer would call it, cross talk

I have sent logs via our supplier which they send on to Yealink but said they could not see anything.

We have never seen this issue with the Gigaset Dect phones so am at a loss myself with the issue

 

[Adrian Fretwell]

This thread references the same issue:
https://www.pbxforums.com/threads/yealink-dect-crosstalk.7704/#post-31385

We have a lot of Yealink DECT including the W70B, but have not had any reports of cross talk.

 

[wouam31]

Hi everyone,

Thanks for your feedback. Yes, I saw @glennbtn 's post, but since I couldn't comment on it, I decided to open a new thread.

On Monday afternoon, I will be on site to try to understand the issues, as I think it will be easier than doing it remotely. I will take this opportunity to capture SIP traces and check the switch.

If anyone has any suggestions for tests, I would appreciate them (we can always forget something to test).

I'll keep you posted whether I find a solution or not!

 

[glennbtn]

@wouam31

how did you get on with your tests?

 

[wouam31]

Hi!

What was actually happening: during a call, when someone hung up from one DECT handset, the audio would switch to another DECT handset.

I believe the switch might have been mixing the RTP streams.

So, I took the W70B base, connected it directly to a port on the router, and created a separate network on that port to ensure nothing else could interfere.

I ran call tests for 3 hours, and the issue didn't occur. Now, I'm waiting until September when everyone is back from vacation to see if the problem persists or if it is definitively resolved.

I have other W70B units on other sites, and no one has reported this problem.

I'm open to other possibilities and additional tests to better understand the issue.

 

[Adrian Fretwell]

I would put money on it being the switch. We have had faulty switches that have sent packets to the wrong MAC address.

 

[wouam31]

Hi everyone,

I just had another site call, with the same setup and... the same issue.

@Adrian Fretwell can you tell me how you configure your bases? 5060, 5061? UDP, SRTP? Codec?

Thank you.

 

[Adrian Fretwell]

can you tell me how you configure your bases? 5060, 5061? UDP, SRTP? Codec?

I don't use the common SIP ports, I vary them between installations but take 8060 as an example. Always UDP, no TLS or SRTP and the codecs in order of preference are G722, G729, PCMA.

 

[wouam31]

Thank you, Adrian, for the information.
I have just updated the records to 5060 and set them to UDP.



In the DECT base configuration, I changed the SIP to 8060.



Am I good, or did I miss something?

Thanks again!

 

[Adrian Fretwell]

Looks good.
There is no harm in changing the local SIP port, but what I meant was my PBX does not use 5060. It is the first measure in preventing the more simple router ALGs (SIP helper apps) from messing around with the SIP packets.

On some of the Yealinks, you can set a different local SIP port for each account, I have done this before when a customers cheap router has got confused.

I would not think that the local (or remote) SIP ports would have any bearing on the RTP though. RTP ports are negotiated in the SDP body. You can change the local RTP port range on some phones, but I have never needed to do so. I have known router ALGs to mess with the SDP too.

 

[wouam31]

I understand better now why the port 5060 was changed.

Can I copy/paste the internal SIP Profile (5060), modify it to 5070, and use it to eliminate any doubts about the router?

Thanks a lot, Adrian.

 

[Adrian Fretwell]

The key to successful diagnostics is "only change one thing at once", then re-test.