Ok, I didn't see that. Yes, not easy scene, but I found the same noise pattern problem in all my scene with white wall.
Also, I found other three different annoying situations, impossible to solve with Corona:
(*) In an room (SPA), after one hour, everything was almost enough, but a glossy surface on a vase was very noisy and, the noise pattern, was incredibly visible (Corona needs an adaptation options or some improvement to solve the noise pattern flickering)
(*) In a room, with a lot of bottle, the flickering on the glass, due lights reflection, was impressive. As other user wrote, like in
this thread or in
this thread, the "solution" (not real solution, because impossible to remove, right now) was to change the glass glossy from 1 to 0.95 or 0.9. Also, I changed the Rays from 25 to 12. But, again, after one hour for frame, the flickering was still there.
(*) White walls, close to a lights (as a led stripe) very noisy (the noise patter is very vibrant) in animation. If I level up a LSM sample to 16 i cannot resolve the problem.
I tryed to remove this in AE, vith a denoise plugin.
As you can see in my frame, there are a crazy noise patter mutation every frame and the bright pixel mutation on the reflection/refraction produced by the lights.