Echo on TDM400P with GSM Link attached on it

Hello,
I have this scenario:

Asterisk system with TE407P and TDM400P. The TE407P is not connected (I will change it with B410P). On the TDM400P is connected a GSM Link only.

When I call “outside” I hear the echo of my voice. The other side hear fine without echo. When I call “inside” between 2 extension I think there is no echo (or is so small that I can’t detect it).

To fix the echo I did:

  • changing the values echotraining = 800, 1200, 2000, 1900, 100, 200 and echocancel = 256, 128, 64, 32 in many variants - still with echo :frowning:

  • using fxotune -i 4 : some strange result - the card has 4 channels 125-128 they are. On the chanel 125 I have connected the GSM Link. It says:

*** cut ***

Tunning module 125

Could not fill input buffer

.Failure

*** end cut ***

On the other channels 126-128 in the fxotune.conf there is only “0”:
126 = 0,0,0,0,0,0,0
127 = 0,0,0,0,0,0,0 (don’t remembar how many 0 they are)

when I type fxotune -h there is only 2 parameters : -i and “number”. Is it the correct version? I read about more parameters.

then when I try fxotune -s :

**** cut ****

openr error on
/dev/Zap/0: no such file or directory

*** end cut ****

I did this too: edit /usr/src/zaptel/zconfig.h and change this:

/* #define ECHO_CAN_KB1 /
/
This is the new latest and greatest */

define ECHO_CAN_MG2

and recomplie. then execute dmesg, but no result for the echo canceler was

I restart the computar and the echo is still there.

Thank you for the help.