asterisk users - Oct 2004 - Echo / Adit 600

We have an Adit 600 with some fxo lines.

Callers calling in on the fxo ports do not hear echo, but the
party answering hears bad echo.

Here is the gain settings on the Adit:
Corporate Adit 600> show 1
SLOT 1:
Settings for FXO:   Channel  1:
     Signaling:       LSCPD
     RxGain:          -2    dB
     TxGain:          -3    dB

And here are the zap settings:
busydetect=no
callprogress=no
echotraining=800
rxgain=0.0
txgain=-6.0

I have tried changing the txgain back and forth, but it is confusing to 
me which gain I need to change.

Thanks for any tips.
P.S. I bought this based on the wiki's good recommendation.

-- 

respectfully, Joseph
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