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I've setup a Draytek 3510 IP PBX with 10 VigorPhone 350 handsets. It's all connected through an unmanaged 48port gigabit switch - all structured cabling except patch leads are Cat6. Dhcp is handed out by a Linux server. All PC's and phones are on the same LAN, in the same subnet. Outgoing calls are made through 4 channels of ISDN2e, using th Draytek FXO ISDN card.

I've not setup an IP PBX before. Probably due to inexperience, I'm getting a lot of echo and delay on the phone lines. So, a few questions:

  1. Should the phones be running through a different switch to the PC's?
  2. Which codec should I be using to avoid echo and delays? (spec here:
  3. Are there any other best practices a novice IP PBX'er should follow?

Thanks for your help....

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I have set up a good few of these now and dependant to the phones you are using could make a difference, If you are using the Vigorphone 350 there is a few things to consider the first is the hand sets in the older version we were getting echo but the newer handsets they seemed to cure this issue, the code we use is

First Priority is 711 u-law Second Priority is 711 a-law

Hope this helps you

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This reads close to an advertisement. What about those handsets solves the echo? – tristan Aug 26 '14 at 15:20

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