The Yuin series are smaller than the stock Apple earbuds as well as the Blox. I don't have the slightest idea what you are talking about
The Sennheiser MX 980 has a thicker base that rests on your ears, the faceplate is thicker than the everything else that I am aware of by a significant margin. It is a hefty % larger than the Living. Have you had both of them together, Goodboy? I have and I am now regretting selling the Living just 2 days ago, I would have loved to have shown you a snapshot of them side by side so you can see the MX980 has a thicker faceplate. The living as a (=l shape to it, its a medium sized face plate base with a smaller back end of the housing, this allows it to almost clip onto your ear and rest nicely.
Here is a good snap of the side view of the MX 980, its base face plate is massive, there is no space for it to hang on your ear at all, literally nothing but a funnel shape. Its just D shaped, and its darn thick and wide, wider than the Hisound Living. Please take a look at your earbuds you showed from a side view, I want to see a snapshot of the mx980 side by side with that other model from a side view, I want to see how deep they are. The Living is thinner and more shallow, the Mx 980 is thicker and deeper. You are not understanding anyone when we say there are fit issues, they fit into the open area of the ear on any normal human, but shallowness is the main problem, they are TOO DEEP, TOO THICK. They just fall off my ears because they are too thick to rest on the bottom area of my ear. You clearly have deeper ears than anyone who has fit problems.
Here are the Living, you can see the front side is a half bullet shape, but the entire back end thins out to a very tiny surface area, this is the part that lets you rest it on your ears, the MX 980 is absent this so there is nothing for it to really rest on or settle down into your ear. The Living is actually smaller than the MX 980 it still rests nicely, a lot like the 9wave Pro. Both have a Megaphone like shape.
9W Pro. See how it has the same basic design as the living in the driver housing area? It has a ( ) face plate with a thinner area behind it so it actually lets you latch it onto your ear.
Lastly, I will argue the point again with you that the MX980 was in fact designed for music enjoyment on the go. In case you haven't noticed, this is head fi, a place where audiophiles are found who enjoy this sound type for pure music enjoyment, a pure, neutral type signature.