Nortel 1535 dropped calls -Registrations Failed- randomly during calls

[autorenova]

I have several different Nortel 1535's that I purchased new a while back. I have been using the phones for a while but now that they are getting used more often I have been searching how to resolve the issues that plague these handsets. I have several different endpoints connecting to my same server that are not having the same issue as the Nortel's. I have searched the forums and cannot seem to find a solutions to the following issues:

Primary Issue:
Registrations Failed error displays on the screen mid call and the call drops. When this occurs I can usually hear an audible crackle. This happens at random times on calls. It can happen in the first couple of minutes or it can be 30+ minutes into a call but I would say that 30% of calls end up dropping on the Nortel 1535. I have been trying to watch the sip debug but have not found anything that stands out. Here are messages that display at the time the call drops: (Domains changed for privacy)
=============================================

Scheduling destruction of SIP dialog '313598-cf01a8c0-13c4-45026-0-131b8278-0' in 32000 ms (Method: REGISTER)

<--- SIP read from UDP:174.52.222.222:1027 --->
REGISTER sip:myserverdomain.com SIP/2.0
From: "Office"<sip:[email protected]>;tag=2f6558-cf01a8c0-13c4-45026-0-6bbbfaed-0
To: "Office"<sip:[email protected]>
Call-ID: 313598-cf01a8c0-13c4-45026-0-131b8278-0
CSeq: 102 REGISTER
Via: SIP/2.0/UDP 192.168.1.207:5060;rport;branch=z9hG4bK-98c-254b46-bd3f507
Max-Forwards: 70
Supported: replaces
User-Agent: Nortel IP Phone 1535 (0.2.50.0905)
Contact: <sip:[email protected]:5060>;expires=60;description="Connected"
Expires: 60
Proxy-Require: com.nortelnetworks.firewall
Content-Length: 0

<------------->
--- (13 headers 0 lines) ---
Sending to 174.52.222.222:1027 (NAT)


<--- Transmitting (NAT) to 174.52.222.222:1027 --->
SIP/2.0 401 Unauthorized
Via: SIP/2.0/UDP 192.168.1.207:5060;branch=z9hG4bK-0-3a0-6f83c0ce;received=174.52.222.222;rport=1027
From: "Office"<sip:[email protected]>;tag=2f6558-cf01a8c0-13c4-45026-0-3f6ef439-0
To: "Office"<sip:[email protected]>;tag=as0615c2ff
Call-ID: 313598-cf01a8c0-13c4-45026-0-e3a0a94-0
CSeq: 1 REGISTER
Server: FPBX-2.8.1(1.8.7.1)
Allow: INVITE, ACK, CANCEL, OPTIONS, BYE, REFER, SUBSCRIBE, NOTIFY, INFO, PUBLISH
Supported: replaces, timer
WWW-Authenticate: Digest algorithm=MD5, realm="asterisk", nonce="13c39bff"
Content-Length: 0


<------------>
Scheduling destruction of SIP dialog '313598-cf01a8c0-13c4-45026-0-e3a0a94-0' in 32000 ms (Method: REGISTER)

<--- SIP read from UDP:174.52.222.222:1027 --->
REGISTER sip:myserverdomain.com SIP/2.0
From: "Office"<sip:[email protected]>;tag=2f6558-cf01a8c0-13c4-45026-0-3f6ef439-0
To: "Office"<sip:[email protected]>
Call-ID: 313598-cf01a8c0-13c4-45026-0-e3a0a94-0
CSeq: 2 REGISTER
Via: SIP/2.0/UDP 192.168.1.207:5060;rport;branch=z9hG4bK-1-3f4-2f6fcd4c
Max-Forwards: 70
Supported: replaces
User-Agent: Nortel IP Phone 1535 (0.2.50.0905)
Contact: <sip:[email protected]:5060>;expires=60;description="Login"
Expires: 60
Authorization: Digest username="1001",realm="asterisk",nonce="13c39bff",uri="sip:myserverdomain.com",response="9cdbde759fa3f545fba335b052f865f9",algorithm=MD5
Proxy-Require: com.nortelnetworks.firewall
Content-Length: 0

===============================================

Does anyone know what "Proxy-Require: com.nortelnetworks.firewall" is for and could it be causing problems.

 

[autorenova]

Not sure if this question will get noticed in my original post so I will post it again but does anyone know what "Proxy-Require: com.nortelnetworks.firewall" is for and could it be causing problems? Also if there is anything that I can post will help shed some light on why the call is dropping please let me know.

 

[dad311]

Sometimes the only way I can register my 1535 is to power cycle. Also, if i reboot my router, the phone will not auto re-register. Real pain.

 

[autorenova]

I don't have any problem getting the phone to register. When the error message "Registrations Failed" is displayed the phone actually does not de-register and I can make a call immediately after without having to power cycle or going into Menu-->Settings-->Voip Settings-->Registration-->Register. In fact most time Asterisk does not realize that my Nortel 1535 has dropped off of the call for another 30-45 seconds. I guess that I should have made that a little clearer in my original message.

 

[autorenova]

Still dropping calls....

It seems odd that I would be the only one that has seen this issue. I currently have 3 Nortel 1535 phones in use and all three of the phones have this same issue. I even tried running one of the 1535 phones off of an Atcom IP4G (Asterisk appliance that runs Asterisk 1.4) to see if it was just my active server causing the issue but it still happened. If I am the only one having this same issue it at least gives me hope that there is something that I can change in my configuration to stop the dropped calls. The Nortel's seem to drop the call sooner on inbound calls. I have several other endpoints on the same server that are not having issues (Obi110, S101I, Linksys SPA941, Cisco 7960). Any suggestions on how or what to look for in order to troubleshoot this would be greatly appreciated.

 

[Derick]

I have two Nortel phones 1535 and havig the same issues - for months

anyone who got this issue fixed?