I have 3 BCM 450 R6.0 and 2 BCM 50 R6.0 networked togather VOIP phones I have Echo problems the first 4 sec of the call all the settings are right and the codac are the same, All the settings on all the BCM are the same. Some of the Echo cleared up but still have 4 sec of Echo at the first of the call. HELP Please any one, any ideas