[Serusers] One way voice Problem

Hi, I have SER and 2 cisco SIP phones configured. When I call between the SIP phones, I can hear voice from only direction (callee to caller voice works, caller to callee doesn't work). Both phones display connected in their LCD screen and I also checked the codecs used by the phones are same. I would appreciate if anyone can point me where this gets wrong and what are the possible solutions for this problem. I have attached the ngrep output below. In the second message of the output, I can see a "Warning: 392" header field with a value "Noisy Feedback tells:...". ngrep output: ------------ interface: eth0 (192.168.6.0/255.255.255.0) ############# # U 192.168.6.103:49834 -> 192.168.6.100:5060 INVITE sip:3311@192.168.6.100 SIP/2.0..Via: SIP/2.0/UDP 192.168.6.103:5060..From: "User ID Balaji" <sip:3322@192.168.6.100>;tag=925f0b 001c0632395f2e8-34ee90e..To: <sip:3311@192.168.6.100>..Call-ID: 000b5f92-63c00003-63cc121e-248e7823@192.168.6.103..Date: Wed, 11 Feb 2 004 18:33:50 GMT..CSeq: 101 INVITE..Expires: 180..User-Agent: Cisco-SIP-IP-Phone/2..Accept: application/sdp..Contact: sip:3322@192.168 .6.103:5060..Content-Type: application/sdp..Content-Length: 226....v=0..o=CiscoSystemsSIP-IPPhone-UserAgent 26498 14989 IN IP4 192.168 .6.103..s=SIP Call..c=IN IP4 192.168.6.103..t=0 0..m=audio 27234 RTP/AVP 0 8 18 101..a=rtpmap:0 pcmu/8000..a=rtpmap:101 telephone-even t/8000..a=fmtp:101 0-11.. # U 192.168.6.100:5060 -> 192.168.6.103:5060 SIP/2.0 100 trying -- your call is important to us..Via: SIP/2.0/UDP 192.168.6.103:5060..From: "User ID Balaji" <sip:3322@192.168.6.10 0>;tag=925f0b001c0632395f2e8-34ee90e..To: <sip:3311@192.168.6.100>..Call-ID: 000b5f92-63c00003-63cc121e-248e7823@192.168.6.103..CSeq: 101 INVITE..Server: Sip EXpress router (0.8.11 (i386/linux))..Content-Length: 0..Warning: 392 192.168.6.100:5060 "Noisy feedback tells : pid=9732 req_src_ip=192.168.6.103 req_src_port=49834 in_uri=sip:3311@192.168.6.100 out_uri=sip:3311@192.168.6.104:5060 via_cnt==1". ... # U 192.168.6.100:5060 -> 192.168.6.104:5060 INVITE sip:3311@192.168.6.104:5060 SIP/2.0..Max-Forwards: 10..Record-Route: <sip:3311@192.168.6.100;ftag=925f0b001c0632395f2e8-34ee90e ;lr=on>..Via: SIP/2.0/UDP 192.168.6.100;branch=z9hG4bK8153.9c3bbf61.0..Via: SIP/2.0/UDP 192.168.6.103:5060..From: "User ID Balaji" <si p:3322@192.168.6.100>;tag=925f0b001c0632395f2e8-34ee90e..To: <sip:3311@192.168.6.100>..Call-ID: 000b5f92-63c00003-63cc121e-248e7823@19 2.168.6.103..Date: Wed, 11 Feb 2004 18:33:50 GMT..CSeq: 101 INVITE..Expires: 180..User-Agent: Cisco-SIP-IP-Phone/2..Accept: applicatio n/sdp..Contact: sip:3322@192.168.6.103:5060..Content-Type: application/sdp..Content-Length: 226....v=0..o=CiscoSystemsSIP-IPPhone-User Agent 26498 14989 IN IP4 192.168.6.103..s=SIP Call..c=IN IP4 192.168.6.103..t=0 0..m=audio 27234 RTP/AVP 0 8 18 101..a=rtpmap:0 pcmu/8 000..a=rtpmap:101 telephone-event/8000..a=fmtp:101 0-11.. # U 192.168.6.104:50020 -> 192.168.6.100:5060 SIP/2.0 100 Trying..Via: SIP/2.0/UDP 192.168.6.100;branch=z9hG4bK8153.9c3bbf61.0,SIP/2.0/UDP 192.168.6.103:5060..From: "User ID Balaji " <sip:3322@192.168.6.100>;tag=925f0b001c0632395f2e8-34ee90e..To: <sip:3311@192.168.6.100>;tag=c25f0b001363563cc13de-474d2b85..Call-ID : 000b5f92-63c00003-63cc121e-248e7823@192.168.6.103..Server: Cisco-SIP-IP-Phone/2..Date: Wed, 11 Feb 2004 18:33:50 GMT..CSeq: 101 INVI TE..Content-Length: 0.... # U 192.168.6.104:50020 -> 192.168.6.100:5060 SIP/2.0 180 Ringing..Via: SIP/2.0/UDP 192.168.6.100;branch=z9hG4bK8153.9c3bbf61.0,SIP/2.0/UDP 192.168.6.103:5060..From: "User ID Balaj i" <sip:3322@192.168.6.100>;tag=925f0b001c0632395f2e8-34ee90e..To: <sip:3311@192.168.6.100>;tag=c25f0b001363563cc13de-474d2b85..Call-I D: 000b5f92-63c00003-63cc121e-248e7823@192.168.6.103..Server: Cisco-SIP-IP-Phone/2..Date: Wed, 11 Feb 2004 18:33:50 GMT..CSeq: 101 INV ITE..Content-Length: 0.... # U 192.168.6.100:5060 -> 192.168.6.103:5060 SIP/2.0 180 Ringing..Via: SIP/2.0/UDP 192.168.6.103:5060..From: "User ID Balaji" <sip:3322@192.168.6.100>;tag=925f0b001c0632395f2e8-34 ee90e..To: <sip:3311@192.168.6.100>;tag=c25f0b001363563cc13de-474d2b85..Call-ID: 000b5f92-63c00003-63cc121e-248e7823@192.168.6.103..Se rver: Cisco-SIP-IP-Phone/2..Date: Wed, 11 Feb 2004 18:33:50 GMT..CSeq: 101 INVITE..Content-Length: 0.... # U 192.168.6.104:50020 -> 192.168.6.100:5060 SIP/2.0 200 OK..Via: SIP/2.0/UDP 192.168.6.100;branch=z9hG4bK8153.9c3bbf61.0,SIP/2.0/UDP 192.168.6.103:5060..From: "User ID Balaji" <s ip:3322@192.168.6.100>;tag=925f0b001c0632395f2e8-34ee90e..To: <sip:3311@192.168.6.100>;tag=c25f0b001363563cc13de-474d2b85..Call-ID: 00 0b5f92-63c00003-63cc121e-248e7823@192.168.6.103..Server: Cisco-SIP-IP-Phone/2..Contact: sip:3311@192.168.6.104:5060..Record-Route: <si p:3311@192.168.6.100;ftag=925f0b001c0632395f2e8-34ee90e;lr=on>..Date: Wed, 11 Feb 2004 18:33:53 GMT..CSeq: 101 INVITE..Content-Type: a pplication/sdp..Content-Length: 221....v=0..o=CiscoSystemsSIP-IPPhone-UserAgent 14538 26512 IN IP4 192.168.6.104..s=SIP Call..c=IN IP4 192.168.6.104..t=0 0..m=audio 24138 RTP/AVP 0 101..a=rtpmap:0 pcmu/8000..a=rtpmap:101 telephone-event/8000..a=fmtp:101 0-11.. # U 192.168.6.100:5060 -> 192.168.6.103:5060 SIP/2.0 200 OK..Via: SIP/2.0/UDP 192.168.6.103:5060..From: "User ID Balaji" <sip:3322@192.168.6.100>;tag=925f0b001c0632395f2e8-34ee90e ..To: <sip:3311@192.168.6.100>;tag=c25f0b001363563cc13de-474d2b85..Call-ID: 000b5f92-63c00003-63cc121e-248e7823@192.168.6.103..Server: Cisco-SIP-IP-Phone/2..Contact: sip:3311@192.168.6.104:5060..Record-Route: <sip:3311@192.168.6.100;ftag=925f0b001c0632395f2e8-34ee90e; lr=on>..Date: Wed, 11 Feb 2004 18:33:53 GMT..CSeq: 101 INVITE..Content-Type: application/sdp..Content-Length: 221....v=0..o=CiscoSyste msSIP-IPPhone-UserAgent 14538 26512 IN IP4 192.168.6.104..s=SIP Call..c=IN IP4 192.168.6.104..t=0 0..m=audio 24138 RTP/AVP 0 101..a=rt pmap:0 pcmu/8000..a=rtpmap:101 telephone-event/8000..a=fmtp:101 0-11..U 192.168.6.103:49834 -> 192.168.6.100:5060 ACK sip:3311@192.168.6.100:5060 SIP/2.0..Via: SIP/2.0/UDP 192.168.6.103:5060..From: "User ID Balaji" <sip:3322@192.168.6.100>;tag=925f 0b001c0632395f2e8-34ee90e..To: <sip:3311@192.168.6.100>;tag=c25f0b001363563cc13de-474d2b85..Call-ID: 000b5f92-63c00003-63cc121e-248e78 23@192.168.6.103..Date: Wed, 11 Feb 2004 18:33:53 GMT..Route: <sip:3311@192.168.6.104:5060>..CSeq: 101 ACK..Content-Length: 0.... # U 192.168.6.100:5060 -> 192.168.6.104:5060 ACK sip:3311@192.168.6.104:5060 SIP/2.0..Max-Forwards: 10..Record-Route: <sip:3311@192.168.6.100;ftag=925f0b001c0632395f2e8-34ee90e;lr =on>..Via: SIP/2.0/UDP 192.168.6.100;branch=0..Via: SIP/2.0/UDP 192.168.6.103:5060..From: "User ID Balaji" <sip:3322@192.168.6.100>;ta g=925f0b001c0632395f2e8-34ee90e..To: <sip:3311@192.168.6.100>;tag=c25f0b001363563cc13de-474d2b85..Call-ID: 000b5f92-63c00003-63cc121e- 248e7823@192.168.6.103..Date: Wed, 11 Feb 2004 18:33:53 GMT..CSeq: 101 ACK..Content-Length: 0.... ### U 128.163.55.134:496 -> 224.0.1.40:496 ..........7=........ ############ U 192.168.6.104:50020 -> 192.168.6.100:5060 BYE sip:3311@192.168.6.100:5060 SIP/2.0..Via: SIP/2.0/UDP 192.168.6.104:5060..From: <sip:3311@192.168.6.100>;tag=c25f0b001363563cc13de -474d2b85..To: "User ID Balaji" <sip:3322@192.168.6.100>;tag=925f0b001c0632395f2e8-34ee90e..Call-ID: 000b5f92-63c00003-63cc121e-248e78 23@192.168.6.103..Date: Wed, 11 Feb 2004 18:34:02 GMT..User-Agent: Cisco-SIP-IP-Phone/2..CSeq: 101 BYE..Route: <sip:3322@192.168.6.103 :5060>..Content-Length: 0.... # U 192.168.6.100:5060 -> 192.168.6.103:5060 BYE sip:3322@192.168.6.103:5060 SIP/2.0..Max-Forwards: 10..Record-Route: <sip:3311@192.168.6.100;ftag=c25f0b001363563cc13de-474d2b85;l r=on>..Via: SIP/2.0/UDP 192.168.6.100;branch=z9hG4bK8153.ac3bbf61.0..Via: SIP/2.0/UDP 192.168.6.104:5060..From: <sip:3311@192.168.6.10 0>;tag=c25f0b001363563cc13de-474d2b85..To: "User ID Balaji" <sip:3322@192.168.6.100>;tag=925f0b001c0632395f2e8-34ee90e..Call-ID: 000b5 f92-63c00003-63cc121e-248e7823@192.168.6.103..Date: Wed, 11 Feb 2004 18:34:02 GMT..User-Agent: Cisco-SIP-IP-Phone/2..CSeq: 101 BYE..Co ntent-Length: 0.... # U 192.168.6.103:49834 -> 192.168.6.100:5060 SIP/2.0 200 OK..Via: SIP/2.0/UDP 192.168.6.100;branch=z9hG4bK8153.ac3bbf61.0,SIP/2.0/UDP 192.168.6.104:5060..From: <sip:3311@192.168.6 .100>;tag=c25f0b001363563cc13de-474d2b85..To: "User ID Balaji" <sip:3322@192.168.6.100>;tag=925f0b001c0632395f2e8-34ee90e..Call-ID: 00 0b5f92-63c00003-63cc121e-248e7823@192.168.6.103..Server: Cisco-SIP-IP-Phone/2..CSeq: 101 BYE..Content-Length: 0.... # U 192.168.6.100:5060 -> 192.168.6.104:5060 SIP/2.0 200 OK..Via: SIP/2.0/UDP 192.168.6.104:5060..From: <sip:3311@192.168.6.100>;tag=c25f0b001363563cc13de-474d2b85..To: "User ID B alaji" <sip:3322@192.168.6.100>;tag=925f0b001c0632395f2e8-34ee90e..Call-ID: 000b5f92-63c00003-63cc121e-248e7823@192.168.6.103..Server: Cisco-SIP-IP-Phone/2..CSeq: 101 BYE..Content-Length: 0.... ###### exit Thanks in advance, Balaji