Okay, I would find cubing during a lecture very disrespectful and rude.
From the perspective of other students, it distracts them. Whether it's loud or not-so-loud, the noise will still distract people. And for people sitting close to you, they might not be able to hear the lecturer.
If I were a lecturer I'd find this very rude. I've spoken in front of classes before, and when you look around the room and see that most people aren't listening, it makes you think "people don't even care, why should I even bother?"
From the perspective of other students, it distracts them. Whether it's loud or not-so-loud, the noise will still distract people. And for people sitting close to you, they might not be able to hear the lecturer.
If I were a lecturer I'd find this very rude. I've spoken in front of classes before, and when you look around the room and see that most people aren't listening, it makes you think "people don't even care, why should I even bother?"