Noisy render with sunlight GI on my interior

Hello Nvidia rendrering gurus!

I have a problem with strong sunlight, bouncing around my interior and causing a lot of noise in my renderings.
It looks good but I cannot solve the noise, even with extreme rendering settings. For my scene 24 sec is long render time for 4 x 3090 GPU, I think. See here my settings at renderfarm:

And the movie look like this:

So what can I do to make the strong sun GI bounces to be less noisy?

If I do not have it, the rendering is super fast and pretty much noise free:


Please answer me and I can send you the full project as PM.

i just realised it may be the glass window material that is the reason for this unwanted extra noise! Gotta work on that tomorrow…

I managed to tweak the scene to make it render faster and with less noise.
But if someone who knows a lot about these rendering settings could help me I would love that.

I deleted the window glass, and I made the my “sun” direct light to be sharp in shadows and a lot less in intensy, so I do not even try to lid my room with this GI bounce. I also removed totally the specular intensity from my “sun”.

I played with render settings at irender farm and I used these:

512
512
40 samples.
They gave me 30 sec rendering time per frame, with 4 x 3090 GPUs.

But I still think there must be something under the hood that kills the noise with faster rendering times.
So please drop me a note and I share you the scene…

Here is my render from iRender + color grading with Lutify.me.
It works ok I think, but your support is welcome :D