I have been tinkering around with a small IP phone pilot, without the full-blown Avaya installation and network assessment. I have no QoS, VLAN, or anything like that going. I have 2 Definity sites that are DCS'd together and am adding a few IP phones at site 2, even though the IP-enabled switch is at site 1. Obviously the IP extensions are being administered at site 1. Anyway, the phones register fine and so is the call quality when calling outside, or to a digital phone at site 1 or 2. But When one IP phone (4620) calls another IP phone (4630) at site 2, the 4620 user cannot hear the 4630 user at all. The 4630 hears the 4620 fine. It doesn't matter who initiates the call, the 4620 is always the one who can't hear the 4630. Any ideas?