KnuKonceptz Kolossus Sound Deadening Melting Failure
In the submitted examples shown, KnuKonceptz Kolossus appears to display very obvious and extreme butyl melting and dripping failure, with the material turning into a nasty liquid-like mess and contaminating nearby surfaces and panels. These examples show severe physical failure and make it very easy to see that the product was no longer stable.
One submitted example is especially concerning because the material was applied to a skid plate that was never even installed on the vehicle. It was left leaning against a wall in a controlled indoor garage environment for several months according to the poster, and the sheets still began to slide downward. According to the description provided with the photos, the material shifted roughly a third to nearly half an inch while just sitting there. That points to a very unstable formula and very poor physical retention. This is most likely due to a poor binding agent, and and formula that is not solid enough.
The other submitted examples show the failure more dramatically. The butyl is visibly melting, dripping, and flowing, leaving behind black goop and contamination on surrounding surfaces. By that point, the product had clearly already lost the stability expected of a proper constrained layer damper.
Again, based on what is shown here, the most likely cause is a very poor butyl formula, with heat making the problem worse where heat is present. The controlled indoor skid plate example also suggests that the formula itself is deeply unstable in general, since it showed movement and failure without the kind of extreme real-world heat most people would expect to blame.
Functional failure was absolutely happening before the visible failure became this obvious. Once the butyl turns into a liquid-like substance and begins flowing and dripping, it is well past the point of no longer behaving like a stable viscoelastic damping layer. A CLD in this state had already lost the behavior that made it useful for controlling resonance.
KnuKonceptz Kolossus has a long enough history of this sort of issue that these submitted examples are not surprising that you can see from searching around, and similar complaints and photos can be found across the internet.
Another thing to keep in mind, based on international shipping records I have been able to dig up (as they are public record), KnuKonceptz Kolossus appears to come from the same manufacturer as NVX sound deadening, though I am not stating that here as a confirmed fact. I only mention it because NVX also has multiple documented melting examples, and the pattern is worth noting.