I've only found a couple threads on this from the past couple years but none (that I have found) had any useful info or resolution.
I have the same 150x sim exported from Houdini 18.5.532 via VAT tools 2.1. One version with "regular" textures, the other padded to powers of 2. The sim does not loop atm.
The attached clip is the screen cap from in engine.
The orange one is the "regular" textures, no padding. Sim looks as expected.
The green one is the textures padded to nearest power of 2. Sim looks as expected *except* for the pop when the loop restarts.
Anyone have any pointers for where to look for a fix? Is this a known/ongoing bug?