[Home]

Summary:ASTERISK-01983: Horrible echo issues with X1ooP
Reporter:ipso (ipso)Labels:
Date Opened:2004-07-09 18:24:20Date Closed:2011-06-07 14:04:50
Priority:MajorRegression?No
Status:Closed/CompleteComponents:Core/General
Versions:Frequency of
Occurrence
Related
Issues:
Environment:Attachments:
Description:I get horrible echo issues when calling from a SIP Phone -> ZAP channel (X100P) out to any PSTN number.

The echo is always there, 100% reproducable, and no matter what Asterisk configuration settings I've tried, I can not eliminate it.

I can be contacted via any of the below methods.
Email: ipso@snappymail.ca
MSN: ipso_frato_2001@hotmail.com
ICQ: 1839899
IRC: Nick: IpSo in the #asterisk channel.

Additional information included.




****** ADDITIONAL INFORMATION ******

I've enabled CONFIG_ZAPTEL_MMX in zaptel/zconfig.h, and one by one compiled each echo cancellation method and tested it. Here are my findings on that:

Ratings between 1 to 10. 1 being unusable, 10 being acceptable.

ECHO_CAN_STEVE                  - 3
ECHO_CAN_STEVE2                 - 3
ECHO_CAN_MARK                   - 1
ECHO_CAN_MARK2                  - 4
ECHO_CAN_MARK2 w/AGGRESSIVE     - 6
ECHO_CAN_MARK2,w/AGGRESSIVE  & echotraining=800      - 6.5
ECHO_CAN_MARK3                  - 4

echotraining=800 just seemed to distort the echo slightly so you
couldn't understand it as well. Though it was sort of hard to tell, it could have been my ears playing tricks on me.

Once I settled on a method, I made hundreds of calls with different rx/tx gains in an attempt to find the best values. I started at 0 for both,
then basically adjusted each one, up and down separately. Completely restarting Asterisk between tries.

I settled on:

rxgain=-14
txgain=-6

However like I mentioned, the calls just got really quiet, the echo can
still be heard, just not as much. But now I constantly get complaints
about the volume being too low.

I've also moved the Asterisk server away from as much electrical
equipment as I can, and I'm using 3 foot chunks of twisted pair solid
core wire straight from the Telco demark to the Asterisk server.

When I make calls to local extensions, or over Nufone, no echo can be heard whatsoever. So by this I think I can rule out the analog phones being crappy, and the SPA-2000's. Only when a call comes in, or goes out the FXO cards is there echo.

Outgoing calls seemed slightly worse then incoming calls. I tried making outgoing call tests to 3 numbers, one being a cell number, and all seemed just as bad.

I'm located in Southern BC, Canada (600ohm lines), and the CO is less then .4Km. away.

Didn't notice any difference when I switched tip/ring.

I also tried setting echochancel=16,32,96,256, and though it did at
times make things worse, it never seemed to really make things better.

I had RichA connect his SIP Phone (SNOM I believe) to do some tests. He confirmed that the echo was very bad when dialing out the ZAP channels to a local PSTN number. However the call quality was excellent when dialing a local EXT to another SIP (SPA-2000) phone.

Zapata.conf:
--------------------------
[channels]
language=en
switchtype=national
context=mainmenu
signalling=fxs_ks
usecallerid=yes
hidecallerid=no
threewaycalling=yes
usecallingpres=yes
faxdetect=no

echocancel=yes
echocancelwhenbridged=yes
echotraining=800 ;Does this cause txgain to max out at -6 perhaps?

rxgain=0
txgain=0

group=1
callgroup=1
pickupgroup=1
immediate=no
channel => 1-4
Comments:By: ipso (ipso) 2004-07-09 18:28:05

zaptel.conf:
----------------------
fxsks=1-4
loadzone = us
defaultzone=us
By: Mark Spencer (markster) 2004-07-09 18:57:41

This is a technical support issue.  Please pursue through support@digium.com and not through the bug tracker.