Electric noise on recording !

[elpimous]

hello, at recording, I have a 'electric' noise on wav :
http://dl.free.fr/kLfr3UPwU

anything like a too much amplified sound.

mic array is leveled to 80%, and tested a 50%, with same result
Stock firmware (mono 16, 32bits)

An idea ?

[elpimous]

new tests : http://dl.free.fr/maZgLmC1E

you can see during speech, and just after, a curved signal
It seems like a chip processing ?!

(I use respeaker mic array for deep learning voce recognition, and I need to cut each vocal part for learning: can't have this king of sound addon, when no speech)
Perhaps an easy solution ? or an idea to minimize it ?
Thanks

[KillingJacky]

Hi It might be the echo of your speech. If your computer has microphones, you can try recording with your computer's microphones and see if there's a tail curve as well.

[elpimous]

Hi, KillingJacky,
no, no microphones problem !
I use respeaker mic array on a developpment plateform (jetson TX2), I just have this microphone.
I you have another idea ...
Perhaps i should try to remove all internal process, like dsp, echo removal...(but don't know how to do !!) LOL
See you,
Vincent