If you un into problems with echo in USB mode you can use the latest 2.0.9 firmware found on our upgrade page:

https://www.konftel.com/sv-se/support#software-versions



This will give the option to use USB RX damping feature that helps with the echo.

This is found in a hidden service menu.


Enter the hidden menu like this

Press MENU.
Longpress on the Hold button (Lower left corner).
Longpress on the Line mode button (Lower right corner).
Now you enter the service menu.

Here you can go down to USB RX damping and make sure that it is enabled.

 

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