Echo question

Not sure if this is a Asterisk issue but i found it very odd.

I was using “X lite” and “Express Talk”, ive tried various options, but i keep getting an echo.

I simply assumed this was feedback on loud speakers and mics etc etc.

To eliminate the issue, i used a proper phone handset and wired it to mic/speaker port.

The thing that confuses me…

I had 2 PC’s, 1 had the handset and 1 was loud speaker only.
I called the other PC, and spoke into my handset, and my voice came out the loudspeaker on the other PC as expected. I simply then heard my echo in my handset, so i thought that was odd as the other PC has no mic on it.

I then switched off all speakers on the other PC, and spoke into the handset, and about 0.5 seconds later i heard my echo in the handset!

Why is my voice/echo being sent BACK to the handset? Im confused? Its very very faint aswell.

I cant see any logic to why the transmitters voice would go back to their speaker?

Cheers! :smile: