I'm using an SPA3102 in conjunction with a GSM premicell. When dialling
out over the mobile network, although I can hear the caller perfectly
well, they experience clipping of the audio at their end.

If a POTS phone is plugged into the premicell, no clipping occurs. If
the SPA is powered off, no clipping occurs.

I have tweaked & tweaked.

Has anyone got any specific "must have" settings for this device to
improve the PSTN audio quality?

If the device wasn't remote, I'd try it in a BT line. Alas, I cannot at
the moment.

Cheers.

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Hi Jono,

> I'm using an SPA3102 in conjunction with a GSM premicell. When dialling
> out over the mobile network, although I can hear the caller perfectly
> well, they experience clipping of the audio at their end.

In the webinterface of the SPA, under the tab "regional", you can find a
setting "FXS port input gain". If you set this at a lower level, this should
decrease the audio level towards your premicell. Try it with steps of 3 (dB)
at a time. A good start value is -3 (that is what I believe is the default).
Negative values mean a reduction, positive values mean amplification of the
audio signal.

Oh... if you don't hear any difference at all, then this is my fault: I
always seem to confuse FXO/FXS input and output signals. If I screwed up:
you need to do the described procedure with the "FXS port output gain" :-)

Hope this helps...
Christian

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> I'm using an SPA3102 in conjunction with a GSM premicell. When
> dialling out over the mobile network, although I can hear the caller
> perfectly well, they experience clipping of the audio at their end.

You know what: I screwed up already :-)  Never mind my earlier post, you
need to adapt the audio level from the SPA towards your PSTN line (the
premicell). The recommendation I made in the previous post would work but
would also affect the audio-levels on your VOIP-calls.

So... second attempt: in the webinterface of the SPA, under the tab "PSTN
line", you can find a setting "SPA To PSTN Gain" (at the bottom of the
page). If you set this at a lower level, this should decrease the audio
level towards your premicell. Try it with steps of 3 (dB) at a time. A good
start value is 0 (that is what I believe is the default). Negative values
mean a reduction, positive values mean amplification of the audio signal
towards the PSTN-line.

Hope I really helped you this time :-)
Christian

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Christian submitted this idea : 
>
> You know what: I screwed up already :-)  Never mind my earlier post, you n
eed
> to adapt the audio level from the SPA towards your PSTN line (the premicel
l).
> The recommendation I made in the previous post would work but would also
> affect the audio-levels on your VOIP-calls.
>
> So... second attempt: in the webinterface of the SPA, under the tab "PSTN
> line", you can find a setting "SPA To PSTN Gain" (at the bottom of the pag
e).
> If you set this at a lower level, this should decrease the audio level
> towards your premicell. Try it with steps of 3 (dB) at a time. A good star
t
> value is 0 (that is what I believe is the default). Negative values mean a
> reduction, positive values mean amplification of the audio signal towards 
the
> PSTN-line.
>
> Hope I really helped you this time :-)
> Christian

Cheers

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