Those are my babies singing. I would go to my shop in the back yard (50 feet away) and get a screwdriver or something and I could hear them so I set up the camera one day. I now have a much larger chorus line.
But now we're out in the country. It's not uncommon for them to "tune up" 3 or 4 times a day.
I can assure you no Dachshunds were harmed in the making.
......Just my ears!....
Edit- It's 11 pm and I came back to this thread and just for grins I hit play. The pups behind me on the bed (same ones as in the movie), heard the ones in the movie and decided, "Oh boy, let's sing again".