I made days after this video was published, a new edit, taking the audio from the trailer and put it into the original. Obviously I did it for me xD

I guess I can answer to your question. In the original video (from putalocura.com) they uploaded as you just saw here, without audio at starting (in all the typical torbe "Pilladas" scenes where he talked with the girl in the street). But, if you see the trailer of this video (it's free on his page), the audio works fine, and that preview it's all the scene of the interview. So, it have no sense that the original didn't have it because obviously it was be recorded.
IMO, the answer is, the "tech" person who works in putalocura, made a mistake in the production and insteaf of resolve and upload again days after, they didn't do because they doesn't really matter their own quality videos, they only want to make money and because that mistake of the audio didn't have impact in their earnings, they didn't care about it...

Why theres no audio at the start?