Material SetFloat issues with HDRP/Lit

For context, I'm randomizing these 3 HDRP/Lit shader values

Code (CSharp):

1. _glassMaterial.SetFloat("_Smoothness",
2.             Mathf.Lerp(0.75f, 0.95f, (float)_rnd.NextDouble()));
3.  
4.         _glassMaterial.SetFloat("_Ior",
5.             Mathf.Lerp(1.01f, 1.05f, (float)_rnd.NextDouble()));
6.  
7.         _glassMaterial.SetFloat("_NormalScale",
8.             Mathf.Lerp(0f, 3f, (float)_rnd.NextDouble()));

I tested this code in Update() and got some strange results.
NormalScale seems to be setting close to within my set range, hitting 3.3s at highest.
Smoothness is changing but its setting to anything between 0 and 1. Mostly they're set to 0.
Ior has never resulted a value other than 0.

What am I missing?

 

have you tried printing the values before setting them on the material ? Maybe the issue comes from the random number generator