Amiga audio output from the video component output!

[Xanxi]

http://youtu.be/8zcL840nUck

I have recorded the intro of Dune from the component output of my A1200 to an USB video capture device on my PC laptop.

There was absolutly no audio cable connected.

And yet, the music from the intro can be heard from this video. It is however very feeble, and you need to pump up the volume.

So, it seems that there is an audio signal in the component output.
How odd!

Would someone have an explanation?

 

[moijk]

I have recorded the intro of Dune from the component output of my A1200 to an USB video capture device on my PC laptop.
..
Would someone have an explanation?

Maybe the mic on something else you got connected picked up the sound?

 

[BLTCON0]

I agree, most laptops have built-in voice mics so this must have picked up the sound (faintly as it is).

 

[Mendel]

how could a microphone pick up a sound if there was no audio cable connected to the amiga?

 

[Xanxi]

I don't see any mic on my recording device. There are 2 RCA connectors for the sound, but as a matter of fact they were not connected.

Do you think that some kind of electronic noise due to a lack of shielding makes that the Paula output is transmitted anywhere on the A1200 mobo, including the component output?

The device is from ebay, similar the the Easycap that sells cheap all over ebay.

---------- Post added at 19:12 ---------- Previous post was at 19:06 ----------

Well, my mistake: indeed the software was catching sound from the laptop mic. Sorry

 

[BLTCON0]

Even if the software was not configured to capture sound AND some interference indeed induced the sound into the composite signal wire, the induced sound would announce its presence only as glitches in the captured video, nothing else.