BRUUUUUH what was that

Question

A few minutes ago I could hear a man testing a mic or something like that, he was saying "Um, dois, três" (One, two, three) and every pause there was a beep. It was so low that I almost couldnt hear, even my headphone having a thing that you can raise the volume, it started and ended too fast so I couldn't show to anyone AND no program was open, despite the chrome, I was in a google meeting, but none of the participants had their mic open when it started, indeed none of the tabs were using sound (like when you play a music or something) when I checked the Task Manager while that person was saying something, only the Chrome and the Task Manager were running.

I couldnt really tell what he was talking after the "Um, dois, três"....

NOTE: I can hear a weird sound now like the wind of a flap of a bird (idk something like that), and I discovered that the sound came from the meeting, but still none of the participants were talking, to be honest, I think it was a bug, so maybe I took an important time of someone but at least I spotted a bug.. I really appreciate if you find anything, if it was a bug at least, It'd be a relief. I don't know if anyone will doubt about it, since I have no proof. the man saying "Um, dois, três" and beep, followed by something I couldn't understand, played 3 times, but it was so low that I was rather trying to hear than trying to record it.. I could have recorded the meeting but I only discovered after it already ended..

*I discovered where it was coming from when I was using the audio mixer and turned chrome sound off and then I right click on the meeting tab and deactivate the sound, again, I only discovered when the man talking sound ended, so I only block the "Bird flap sound" now.

I apologize if it looks like a fanfic or something, but I'm shaking since I have no idea if the sound came from the meeting or not so I'd like just to know if it was a bug and the sound came from other meeting of someone else, IDK

I appreciate any responses according to what it was.. thanks

I forgot to mention that im brazilian, so thats why I could understand he saying um, dois and três

And I'm sorry if it was a simple bug and I just wrote an entire text about it, I apologize