Still getting echo?

[meezy1]

Hi.
I have a raspberry pi 3B and have the 2-mic hat. I followed the the instructions as given on https://github.com/voice-engine/ec.
I'm trying to make a voip/cloudbell but I ran into echo problems. So this led me to using this repo.

I have a speaker soldered to the board(2-mic) and tried other external speakers too.

My current goal is to achieve recording and playing sound at the same time.
I used the following in a terminal:
./ec -i plughw:1 -o plughw:1 -d 200
and in another:
aplay -f cd -r 16000 /tmp/ec.output -d 200

I also tried playing around with buffer time, period time, period size, buffer size, filter length and channel numbers.
I either get no sound, delay in sound or echo on different settings.

The log is usually warning: The echo canceller start acting funny...
OR
playback filled # bytes zero

I've tried python libraries(speexdsp) and get similar results or echoing sound but it's sounds squared. Plus these libraries don't give live playing and recording examples.

Thank you in advanced.