Post process volume acting strange

Hi,
I made a post process volume for my scene which contains water. The volume stops at the surface of the water and has some color grading and blurry camera settings so it looks like the camera is in the water.
For some reason the color grading applies normally (active inside the volume as intended) but I noticed the camera settings such as DoF and vignetting were applied everywhere. So i unchecked the “unbound” option, and now the camera DoF and vignetting are applied only outside of the volume ! I want everything to only apply inside. What am I missing here ?

This is my camera underwater (inside the volume)

= color grading, no vignetting or DoF

This is the camera out of the water :

= no color grading but DoF and vignetting are applied.

what is going ooooon

thank you !