atcomsystems.ca/forum Forums TDM Business Telephone Systems Mitel Telephones & Systems Echo on IP phones between nodes

Axxess 256 v11 and a 5000 at 6.1.
We added 50 ip phones, all with DHCP, they already had about 50 IP phones.
They had some SIP trunks that caused the 5000 to lock up and so I was kind of forced to upgrade the 5000 to 6.1.
The Axxess is networked to the 5000 with an IPRC and Private Networking.
I primarily get echo, on the IP phones, when they call analog extensions on the Axxess.
I got their data people involved, who tested the IP phones in their network closet and in the end it turned out that one of the IP phones they were using to test seems to be bad and echos frequently.
I have tried changing the echo profiles in the 5000, all the IP phones in the 5000 are set with P2P (not exactly related to my problem I know). I'm thinking that the problem is a couple of things - 1 the people using the IP phones and being intolerant of some echo, 2 - an intermittent problem on the data side 3- some of the IP phones might be bad (they didn't by the phones from us)
The main thing is that until we added the 50 phones who are all on one cisco/Linksys poe switch, I didn't have people complaining about echo calling between the 2 systems.
Which makes me think it's a data problem.
I think I will have to pay to call tech support since 6.1 on the 5000 isn't supported networking wise, to the Axxess so, I'm just seeing if any of you have suggestions of where I might focus my attention on this, first. thanks.

What model of IP Phone are you using? Have you heard the echo yourself? I have had situations where the customer reported echo but it turned out the sidetone was too loud for their taste or they were not used to the HD voice of newer phones.

The IP phones are all 5320's. Happens that one of the IP phones testing was done with was bad and always produced echo.
The actual problem is that calling on the Private Networking PRI to the Axxess produces echo. Calling across the IPRC's private networking trunks does not.
The 5000's IP phones, if they make a call to analog/digital phones on the Axxess will hear echo. The Axxess phones do not hear it.
We are looking to see if we can still get licenses for IPRC private networking or not.

I messed around through online monitor and adjusted the gain on the private networking PRI channels and got the echo into a tolerable state.