Hi
I have a customer with a voice quality issue that I'm having a hard time fixing. The complaints are only coming from two (very important) people who happen to make a lot of long distance calls. They say that call placed to a handful of area codes (3 or 4 have been identified) contain static and noticeable delay much like a poor cell phone call (I'm assured the destination is not a cell phone).
The issue seems to only affect the IP phone user.
I haven't been able to monitor the gateway while one of these calls is occurring but whenever I get a complaint I've checked the CMRs and the latency, jitter, drops are all 0 and the codec is G711.
I don't think the calls are using dial-peer 0 but I don't know of any way to confirm that without monitoring the gateway during the call. I've pasted a portion of the config from their 2651xm PRI gateway below.
My other thought is that the echo cancellation might be responsible. Is that possible? I'm using the enhanced echo cancellation and have it set to 64ms.
The load on the gateway is 12.3(4)T. Call Manager is 3.3.3sr2
network-clock-participate wic 0
network-clock-select 1 T1 0/0
voice-card 0
dspfarm
no local-bypass
!
aaa new-model
!
!
aaa authentication login default line
aaa session-id common
ip subnet-zero
!
!
!
!
no ip domain lookup
ip domain name xxx.com
no ftp-server write-enable
isdn switch-type primary-5ess
!
!
!
!
voice class codec 1
codec preference 1 g711ulaw
codec preference 2 g729r8
!
!
!
voice class h323 1
h225 timeout tcp establish 3
!
!
!
!
!
!
!
!
!
controller T1 0/0
framing esf
crc-threshold 320
linecode b8zs
pri-group timeslots 1-24
!
!
!
interface FastEthernet0/0
ip address x.x.x.2 255.255.255.0
duplex auto
speed auto
h323-gateway voip bind srcaddr x.x.x.2
!
interface Serial0/0:23
no ip address
no logging event link-status
isdn switch-type primary-5ess
isdn incoming-voice voice
isdn bchan-number-order ascending
no cdp enable
!
interface FastEthernet0/1
duplex auto
speed auto
!
ip classless
ip route 0.0.0.0 0.0.0.0 x.x.x.1
ip http server
!
!
logging trap debugging
logging x.x.x.45
snmp-server enable traps tty
!
!
control-plane
!
!
!
voice-port 0/0:23
no vad
no comfort-noise
timeouts interdigit 3
!
!
!
!
!
dial-peer voice 1 voip
answer-address xxx.......
destination-pattern ....
progress_ind setup enable 3
voice-class codec 1
voice-class h323 1
session target ipv4:x.x.x.42
dtmf-relay h245-alphanumeric
no vad
!
dial-peer voice 2 voip
preference 1
answer-address 3...
destination-pattern ....
progress_ind setup enable 3
translate-outgoing calling 1
voice-class codec 1
voice-class h323 1
session target ipv4:x.x.x.41
dtmf-relay h245-alphanumeric
clid network-number 4144761880
no vad
!
dial-peer voice 3 pots
destination-pattern .......
progress_ind alert enable 8
progress_ind progress enable 8
progress_ind connect enable 8
incoming called-number .T
direct-inward-dial
port 0/0:23
forward-digits all
!
Thanks and sorry about the long post.
