Hi there.
I am using TDM404B card (4 FXO ports). I am currently using Asterisk’s software echo cancellation and I also activated the Asterisk’s echo training option (in zapata.conf, echotraining=yes option).
The voice quality has been good for outbound calls but not for incoming calls. For example, when I answered an incoming call, I often can hear whatever I said repeating itself (echo) at my end. After a short while, eventually the echo will disappear. This echo is only for inbound calls and is only at my end.
Would like to ask for the experts what else I can do at Asterisk side? If I purchase a hardware echo cancellation module for my TDM404B card, will it be able to do a better echo cancellation job?
Many thanks