Solved unsupported media type

[TheSPW]

Hi, one of my users reported being unable to call a particular number (Viking Direct on 0330 128 1399), it rings once and then errors with "unsupported media type". I tried it on mine and get the same error. I've tried other 0330 numbers without issue. Any ideas?

 

[Evolute IT]

Hi, one of my users reported being unable to call a particular number (Viking Direct on 0330 128 1399), it rings once and then errors with "unsupported media type". I tried it on mine and get the same error. I've tried other 0330 numbers without issue. Any ideas?

Check your codecs with your provider. Make sure they are aligned on the 3CX also.

 

[JohnS_3CX]

Who responds with unsupported media? Who makes the offer for that unsupported media?

Looking at the Activity Log (with Verbose mode enabled) should provide some useful information on the above.

 

[eddv123]

If you run a Wireshark capture from 3CX on a failing call and see something like a 488 not acceptable here then this is a good indication that the codecs are mis-matched as @Frederick Marcoux said.

 

[AWS2P]

Perhaps it can also be the remote line not available at all if you done several call tests from different public providers with same behavior each time.

 

[leejor]

It may also be some issue with the terminating end, which you would have no control over. Check the logs, to see if the attempted Codec is listed, as a starting point. It might be as simple as enabling that, in 3CX or your sets.

 

[TheSPW]

Hi all, thanks for your responses. I've tried enabling all the codecs available to me in 3CX but that didn't make any changes. I've gotten a verbose log from the 3CX but its beyond my understanding, can I post it here? If so is there anything I should remove (apart from the obvious like my name)?

 

[eddv123]

Get a PCAP trace also: https://www.3cx.com/docs/capture-network-traffic/ this will show who is sending the response and the response itself.

If posting anything on a live forum be very careful it does not contain sensitive information, if you want to PM me the PCAP this is fine also.

 

[eddv123]

**Trace sent via PM**

From the trace I can see you are using GAMMA telecom (based on the public IP address you are sending to).

Your SDP body states that you are trying to negotiate with G729 first and this can also be seen in the call negotiation as well (see attached screen shots).

I know from using Gamma previously that they only support G711 and G729 codecs, however G729 is not set as standard and must be set on the portal manually under:

Provisioning and Service management >> Voice Connectivity >> Gamma SIP trunks >> "enter DDI" >> Service >> Codecs

Either do this or simply set your trunk on 3CX to put G711 first in the list.

Note: You are also trying to negotiate (have set) GSM, Speex and iLBC codecs on your trunk - Gamma dont support these so there is no point in having them set.

 

[YiannisH_3CX]

If the issue is with a specific number then i would speak to your provider about this. Since all other numbers work your codecs and configuration are fine. The error probably comes further down the line and your provider just relays the reply.
Speak to them as they are the only ones who can past their server and tell you what the issue is.

 

[TheSPW]

Thanks Eddv, I added the speex, ilbc, G722 and Opus in this morning to see if it made a difference, I've taken them out again. I have G.711 A-law and G.711 U-law in my list in the SIP details, either of those to the top? The list in the 3CX options doesn't seem to have G711 which I guess is my issue?

 

[eddv123]

Yes, no point in speex, ilbc, G722 and Opus for Gamma.

G711 alaw is UK and Europe ulaw is U.S mostly. I would only change this for the SIP trunk for the time being and see how you get on.

 

[JohnS_3CX]

Take a look again at post #10

 

[TheSPW]

Thanks all, the codecs have been changed by the supplier and all seems to work now

 

[eddv123]

Thanks all, the codecs have been changed by the supplier and all seems to work now

Good news, why did they change this for you ? you should have access to do this via your provider portal.

 

[TheSPW]

I have access to a Gamma Sip Trunk Call Monitor but that's all