Materials automatically lowers/removes textures

Another way of saying it: Textures within materials become low quality after a few moments (usually clicking on another static mesh or different window).

EDIT: I just notice that when I activate play mode, I get a "TEXTURE STREAMING POOL OVER ###MB). Could that be causing it?

I recently upgraded from 4.11 to 4.15 and I had the plugin Substance, which is now disabled because I thought it was the root cause. I am still getting this problem.

What’s quirky about this particular event is that I’ll notice a low-quality material, double click it, check out its blueprint, find the textureSample and open that in a window – and it’s only until I click the static mesh in the viewport it reverts back to full quality. No selection, no changes… just the mere fact of opening and observing it (and clicking out) the texture then updates.

However, once I continue my work, it jumps back to removing or reducing the quality of the texture.

This is now beginning to affect smaller static meshes with custom materials and not just Starter Content materials.Engine Scalability is already set to Epic. I’m wondering if this has something to do with an override or something.

I’m more of a hobbyist than developer so all this is very new to me; any help would be appreciated!

Simply put you don’t have enough memory for all the textures. Instead of crashing, the engine is streaming lower resolution mips as they take less memory.

you can use a streaminpool with a bigger size, as by default in the old version of UE it s pretty small :
try to type this in the console : r.Streaming.PoolSize 1000
here for mor infos :