[Asterisk-Users] Static problems with Asterisk + Polycom phones

Roman Volf
Thu, 09 Feb 2006 13:13:06 -0000

Hey all,

I'm having problems where there is significant static when making SIP ->
PSTN calls. SIP -> SIP and SIP -> VM calls are totally clear and fine.

Here's the setup:

Polycom 601,501, and ten 301s.
Digum 2400 TDM card w/echo cancelling, 12 FXO ports.
The TDM card is on IRQ 5 with nothing else on it.

Server Specs:
Asus P4P800E Deluxe
P4 3.0 Ghz
1 GB Ram
80 GB SATA HD

- There is no static when using a normal phone direct to the 66 block.
- The sound is also a bit low, and bumping the volume on the Polycom
phones makes the static alot worse (obviously)

zapata.conf settings:
[channels]

language=en
context=from-pstn
signalling=fxs_ks

usecallerid=yes
hidecallerid=no
callwaiting=no
usecallingpres=yes
callwaitingcallerid=yes
threewaycalling=yes
transfer=yes
cancallforward=yes
callreturn=yes
echocancel=128
echocancelwhenbridged=yes
echotraining=500
rxgain=6
txgain=3
group=0
callgroup=1
pickupgroup=1
immediate=yes
faxdetect=no


zaptel.conf settings:

fxsks=17-24
loadzone        = us
defaultzone     = us



- Running Fedora Core 4 - Kernel 2.6.14-1.1653_FC4smp
- USB is completely disabled.

cat /proc/interrupts:
           CPU0
  0:    3115334          XT-PIC  timer
  1:          8          XT-PIC  i8042
  2:          0          XT-PIC  cascade
  5:   12453626          XT-PIC  wctdm24xxp
  8:          1          XT-PIC  rtc
 10:      93751          XT-PIC  libata
 11:     907892          XT-PIC  SysKonnect SK-98xx, eth1
 15:     111542          XT-PIC  ide1
NMI:          0
LOC:    3115228
ERR:          0
MIS:          0





Any other information you need to help me figure this out, please let me
know.

- Roman