Howto:Having ECHO problems
Applies To
This information applies to
- all innovaphone products
any build
More Information
If you have an echo problem – pleas check this first:
Do you meet the Echo problem always ?
- between IP phones ?
- between Isdn and IP phones ?
- between analog phones and/or Dect phones to IP phones or Isdn (connected an analog adapter IP21,IP22,IP24)?
IF this problem is with analog or Dect Phone - they have no good jitter buffer - occurs with very old Dect phones in very few cases - the best solution here is - eliminate this phone.
If you have a general echo problem - you have a delay Problem in your Network
To find this out
Pleas watch PBX – Call screen (administration - pbx - calls)
Extension A NameA H323EFC:TRANSIT G729AB (42,6,3) >> Extension B NameB H323EFC:TRANSIT G729AB (47,2,5) Connected
The explanation for that screen is here Reference:Administration/PBX/Calls
The values in the brackets are
Round trip (RT) = Transit time of a data packet from A to B and back again.
Jitter = Latency time (time interval from the end of an event up to the start of the response).
Loss (PL) = Number of lost packets (packet loss).
Jitter
If the jitter greater that 20 – the echo compensation does not work – normal is the jitter less that 5ms.
If the jitter is greater tat 5 – please check your network – switch off flow control and buffers – real time protocols don't like this – if you have routers and different bandwidth – switch on RTP priority or configure an TOS value on the Phones and prioritize this traffic.
General Codec information
Use G.729 60ms WAN (default value)
– pros: optimal bandwidth – tolerates packet loss – contras: “subjective” turns the volume down – please correct via -> button on the phone
Use G.711 20ms for LAN
- pros: like ISDN – echo isn’t audible - “subjective” turns the volume up - contras: sensitive if you have packet loss – bandwidth intense
We support the The G.168 Echo Canceller on all our product with am maximum of 24ms jitter.
You can Disable the Echo canceller but no adjustments to set- its default enabled.
Our echo compression is dynamic - contend sensitive -. no values to set.
It is no solution to make volume adjustments on the Endpoints for solving the Echo problem