Echo on VOIP with OXO

[Trompie]

Hi

I have an OXO installed with 50 users, release 610/042.001. CPU 3m with VOIP 16 card. 2 buildings connected with fiber.
There is echo on all the ip phones when phoning out. The use analog trunks to phone out. So what I suggested is that the data switches must be earthed on both sides. Phones are in separate VLAN.
Echo was gone after cabinets was earthed.
Now suddenly echo is back????

Please tell me what can be the cause for this as this is my only OXO with this problem??
What can I check??

Thanx
Martin

[tot3nkopf]

What external lines do you use? Analog?

[enio.eltz]

Is echo calcellation enabled in voip parameters?
Have you managed trunk gain in TrkGainIP?
I have some PABXs with analog trunk thrugh voip, but there aren't problems.

[Trompie]

Hi

They are using analogue lines yes.
And all the echo cancellation is activated on the extensions and in the voip parametres. Voice active detection is activated on voip parametres.
Voice active detection is not activated on the extensions though...will that help?

I have not fiddled with TrkGainIp yet due to the fact that this is the only OXO I have with this issue. And seeing that it was away and suddenly it is back just made me think it was a network issue??

Thanx for feedback thus far

[Trompie]

Hi

I solved it by changing the trunk access of each line under "transmission plan" " type" to "short line. 0.4 / 0.5 / 0.6 mm

this is however the only oxo I have with analog accesses that I had to change this