[asterisk-users] Asterisk, Linksys SPA-3000 echo

[Thczv F. Thczv]

On 8/2/06, Dean @ INKnBITs <dean.bath at inknbits.co.uk> wrote:

> I have been looking through all the web sites about echo problems and how to
> solve them on the spa-3000, but I still have not managed to fix mine! I'm in
> the UK and have setup all the tones, port impedance to 370+620||310nF, had
> the echo Canc options on and off, turned down the SPA - PSTN gain until it
> would not even dial, still had the echo. It not a little echo, its enough
> you cannot really use it. (I have 3 units, and they all do the same)
>
> I'm using the SPA to route PSTN calls to asterisk, then polycom IP501 to
> asterisk.
>
> Hardware version: 3.0.0(1178)
> Software version: 3.1.3(GWa)
>
> I have tried 3.1.10 and 2.0.13, but still have the same problem, the other
> party has a clear call, but I can hear myself as an echo.
>
> Has anybody got these to work ok? If so, please, please, please could I have
> the settings you used, it's been driving me crazy for the last two weeks.

Hi Dean,

The only firmware that worked for me was 3.1.3.  Here is what I did:

On the Regional tab, at the bottom, I have FXS Port Input Gain set to
-8 and FXS Port Output gain set to 0.  Then on the PSTN Line tab, I
have SPA to PSTN Gain set to 10, and PSTN to SPA Gain set to 4.

My setup may work differently than yours.  The only time I dial out to
the PSTN over the SPA is in case of an emergency (911) or if my
network or internet access go down.  Otherwise all outbound traffic
goes out IP.

However, almost all of my inbound traffic comes from the PSTN over the
SPA.  So, I was having echo problems when I received calls.  These
settings helped a lot, without completely eliminating the problem.
But at least now it passes the wife test.  :-)

I forgot to mention the real challenge I faced with this, which is
volume.  It was a big balancing act for me.  I could adjust the gain
on one of the settings, and the echo would go away, but the volume
would be too quiet or too loud.  It took a lot of trial ane error
before I got the volume about right, while avoiding most of the echo.
I would adjust the gain up or down by one, save and test.  Then adjust
by one, save and test, over and over.

I still have one strange problem.  All callers to my PSTN line go to
an IVR menu that sounds fine.  But as soon as someone presses a
button, and the call is transferred, the ring tone is amazingly loud.
I have all the other volumes about where I want them.  It is only the
ring tone in this one situation that blows your ear off.  I wish I
knew how to adjust that one thing.

--davidh