They are when they need to be, for all followers of Slaanesh see beauty in silence as well as the heart wrenching beat of glorious music.
I think they try and seek the exotic and the bizarre rather than the familiar. Silence doesn’t register on their minds; they need a constant stream of new and vibrant experience to keep themselves satisfied, so something familiar - like silence - would bore them.
have you ever experienced total and complete absolute silence? it is bliss. and it is disturbing.
Given that most Noise Marines have lived for millenia, they will have had their fill of silence. Assuming they do enjoy silence, they will need increasingly more diverse and silent types of silence to stimulate themselves. This isn’t really possible…
I’m also wondering how he sees since he has pipes in his eyes (i believe)… Maybe he hears his way around?
"When you play the game of thrones you win or you take over the world, launch a crusade across the stars, only to have your favoured son turn against you, start a catastrophic civil war and nearly kill you so that you end up upon a Golden Throne for ten thousand years whilst the empire you built warps into a twisted version of your vision." - The Emperor of Mankind