Im deploying a new system with 5 Aastra 6755i phones. Phones are configured with the Aastra 2.3 XML Scripts and Elastix 2.02. The phones update the Firmware and download config perfectly, but after about 5 to 10 min they randomly start loosing there SIP registration and start displaying "No Service". You can still make outbound calls but inbound is a crap shoot. Phones will then randomly reregister. Elastix and Phones are on same LAN. Phone firmware is 220.127.116.117. I have seen some posts for this on earler firmwares but it looks like it was resolved with later firmware, except im already using the latest firmware. Any Ideas on how to make these start working properly. I need the system to go live by the end of the week. Thanks in advance.