At work, can’t go to your YouTube linkl, so I don’t know exactly what you’ve been watching. Also, I don’t have a specific memory of how that scene ends from when I saw it in the theater.
However, a little background establishing the concept of the project:
Rodriguez’s Planet Terror and Tarantino’s Death Proof, released as a double bill titled Grindhouse were meant to emulate grindhouse films of the seventies.
One aspect that both directors chose to mimic was the poor quality of the prints of these seventies films: a limited number of prints would be passed from theater to theater from town to town. They were often not treated with care and very soon ended up looking like crap- add the disrepair of the prints to the fact that the production values were terrible to begin with, they really looked like complete crap.
The poor quality of the prints came not just from being mishandled, but (and this is key to your query) projectionists would cut out frames from the film to keep before sending the print off to the next theater. The frames that were most often cut out were scenes with sex and nudity.
Theater goers who were watching a print that had already been abused, would see the set up of the sex scene, get all excited for it, then the film would jump to the next scene with no payoff leaving the audience unsatisfied.
Tarantino and Rodriguez both purposely set up scenes of sex/nudity then inserted a crude edit right before the payoff- as an “in joke” paying tribute to the damaged prints they had watched in old grindhouse theaters.
The crude edit often damaged the audio track as well: the “needle scrape” sound you’re hearing.