Most modern voice applications give a pretty clear visual indicator about who is making noise. I think in your scenario, the person echoing the audio would be quickly identified and told to mute themselves. If they were the only ones playing your audio back after a delay, people would suspect that they are the ones with the connection issue.
However, this was pretty common for a prank, especially 10-15 years ago on services like Ventrilo which resulted in the then-popular Ventrilo Harassment series. Most of the people who got pranked in those didn't get a visual indicator of who was playing sound. The situation you describe can be seen in this video titled "Ventertainment - Nerd Confusion 3: The Ring":