Gamma SIP Trunks - Crossed Audio Lines

[Tefters]

Afternoon all,

 

Anyone else out there this afternoon getting crossed RTP audio streams on Gamma SIP trunks?

 

Was just upgrading my 3CX PBX to v18 and have so far been unable to test calls properly afterwards as my school DDI range is going all over the country to other businesses??? 9 and counting so far...

The call sessions are showing up my PBX but the audio streams are definately on the piss and going god knows where.

 

Have reported to Gamma but so far no response.

I have flagged as urgent seeing as I dove straight into a patient/doctor audio stream at a GP surgery and they had no clue I was there.

Edited April 19, 2022 by Tefters

[howartp]

Have reported to Gamma but so far no response.

I have flagged as urgent seeing as I dove straight into a patient/doctor audio stream at a GP surgery and they had no clue I was there.

Wow! I've not moved to SIPs yet so haven't dug into the what how, but I didn't realise this was a theoretical possibility (even rare/unlikely).

[synaesthesia]

Ooer! I didn't think that would be possible either, but have just checked our call logs to be sure and thankfully all looks OK at a glance. Please do make sure you report to your DPO.

[Tefters]

I didnt think it was possible either and Gamma are still a bit in disbelief that the issue is happening.

I am by no means a SIP expert, I just follow the usual guidance and everything works but if I were to describe it how I am seeing it there are 2 lanes of data. 1 lane is the session setup/call handling (duration, numbers etc...) and the other is the RTP voice data. The session handling is working as intended as I am seeing the calls on my PBX being setup, the number calling in (my mobile), duration etc... exactly as you would expect but the RTP voice stream/lane is going off to god knows where and randomly changing each time.

 

After writing this I thought I would just test again today and out of 5 calls I had all 5 terminate successfully on a session setup side but only 4 were successful on the RTP audio side, I just hit Harlow council dialing my 01908 682222 number.

 

If you fancy a little giggle then feel free calling our main number above a few times and seeing what you get out of curiosity.

Edited April 20, 2022 by Tefters

[Steve21]

If you fancy a little giggle then feel free calling our main number above a few times and seeing what you get out of curiosity.

 

Tried a few times and all seems to hit the school from my end at least (not sure if that’s good or bad to you lol)

 

Wonder if it’s make a difference with us being in Gamma though as it might be internal only routing?

 

Guess could try in mobile too if you wanted more tests

 

Steve

[Tefters]

Tried a few times and all seems to hit the school from my end at least (not sure if that’s good or bad to you lol)

 

Wonder if it’s make a difference with us being in Gamma though as it might be internal only routing?

 

Guess could try in mobile too if you wanted more tests

 

Steve

If you dont mind Steve.

I'm on Virgin Media for my mobile and it does seem sporadic when it happens.

 

Just got off the phone from Exa and they straight away said its going to be Gamma routing of the RTP traffic that they should be able to pickup on packet capture which is what I expected so back to Gamma I go.

[Steve21]

If you dont mind Steve.

I'm on Virgin Media for my mobile and it does seem sporadic when it happens.

 

Just got off the phone from Exa and they straight away said its going to be Gamma routing of the RTP traffic that they should be able to pickup on packet capture which is what I expected so back to Gamma I go.

 

10 via EE and all hit the school

 

How often were you finding it?

 

Steve

[Tefters]

10 via EE and all hit the school

 

How often were you finding it?

 

Steve

 

Less than that. Just did another 5 and the 4th went AWOL.

 

The giveaway is if there is ringing for longer than 3 rings or silence after the call pickups for longer than 2 seconds then just wait and it can take about 40 seconds from that.

 

Our actual PBX auto attendant answers very quickly and without delay once the call answers so any sort of delay or extended ringing is the usual suspect to look out for.

[Tefters]

Gamma have now setup packet capture again and I have provided them with 5 examples since.

 

Could this be a mobile network provider issue somehow?!

[andy_b]

I called 20ish times from a Landline and hit the AA everytime.

[Steve21]

Less than that. Just did another 5 and the 4th went AWOL.

 

The giveaway is if there is ringing for longer than 3 rings or silence after the call pickups for longer than 2 seconds then just wait and it can take about 40 seconds from that.

 

Our actual PBX auto attendant answers very quickly and without delay once the call answers so any sort of delay or extended ringing is the usual suspect to look out for.

 

Another 10 and no issues on EE so far

 

Steve

[Tefters]

Thanks all.

 

I can see you all calling in and hitting the AA straight away with durations of 3 seconds.

I'm now thinking this is a mobile network routing issue?!?!

 

Update - My misses and kids just returned from being out.

My kids are on ID mobile, no issue after 20 calls.

Misses is with Virgin Media as well - First call placed and the issue was present.

 

Back to Gamma with the info.

Edited April 20, 2022 by Tefters

[howartp]

No problems from O2 mobile either - all calls hitting your AA.

[Tefters]

Ok so things just got interesting!

I managed to speak to a friend who has both Virgin Media landline and Mobile.

He made 10 calls from his landline and everything was fine. He made 10 calls from his mobile and only 4 were successful, the other ended up with other companies/individuals but I saw all the sessions live on my 3CX PBX.

 

Now having just done a Google it would appear Virgin Media use to be on EE and then transitioned to Vodafone as their underlying mobile carrier.

This confused me as I saw a Virgin/O2 advert the other day but turns out they are/have merged but not moved the network yet due to a 5 year deal.

 

From what I can accertain and going by peoples reports above EE and O2 networks are fine so my next question is do we have any Vodafone mobile people out there that could test for me to see if its with the underlying carrier or Virgin themselves.

 

Many thanks to all for the assistance, this is getting more and more interesting the further down the rabbit hole we go.

Edited April 20, 2022 by Tefters