New user - high pitch noise with amps + lower capture volume

Hi,
New user here with some questions. I come from Tone X and while those captures are still more “real” I decided to get a quad cortex because of the possibility to use more than one and the extra effects.

#1
What I notice is that there is high pitch noice when using an amp block. When I change the volume encoder to lower output I hear that pitch going down as well. This also happens when I change the output menu. At unity gain the pitch is somewhere between 3k and 4k. If I make the output louder that pitch also goes up until it gets lost in the white noise or out of my frequency hearing.
First I thought it was with any setup but it comes from the amp block and as far as I can tell not every amp has it. US Tweed Basslad for example does this.

The high pitch is there even when there is no input. You lower the volume and you hear the pitch going down in frequency. Is this a known bug? The cortex has the latest OS.

#2
Is there a way that the capture out can output at a lower volume? It is too hot for certain things I want to capture.

#3
Is the quad cortex 32 floating bit? I sometimes hear digital artifacts in the overdriven sound while the end gives me no clipping error at all. I wonder if a block is overloading or not. I actually wish I could meter every block. With floating bit it wouldn’t be a problem but I still gain stage.

cheers