Around 3 hours into the production of the headphone, I run into a problem. I have most of the materials I needed but I needed something that will block the soundwaves from an instrument and currently, I don't own any of that kind. I know of a few materials that can act as something that would allow me to actively block the sound of any instruments but they are not that easy to get as they are one of the rare items dropped by a monster. Luckily, that said monster is currently present in this continent and I can hunt it down. The only problem is the drop rate.
This item is called the [Skin of the Screaming Monkey]. It only appears in drops and it never appears in any other way by killing the monster [White Howler]. Even butchering the carcass does not yield the skin as the normal skin will just appear as [White Pelt].