First I must say that I am very new to the Elastix world. We are having trouble with an intermittant beep and a very loud echo on our phones. To this point we are the only ones who can hear the echo, thank goodness, but it is very annoying. The echo doesn't happen all the time and it never happens if we call interior extensions. Currently we have a Cisco SPA8800 converting 4 land lines to the network and the server contains no cards. We are using AAstra 55i phones and a Netgear Prosafe POE switch. Any help would be appreciated.