Wrong PBR texture colors in 3d weapon models

[Hashi]

I'm using my own 3d weapon models and for the longest time I had this issue with wrong PBR colors.
In the attached screenshot you can see that the PBR shader makes the intense blue light RED unlike the specular shader that works properly.

With trial and error I was able to mitigate this by removing the kD multiplier from the material_pbr.fp (gzdoom.pk3), apparently that coeff causes the red tint in this particular case (on other models the color was different, usually on metallic parts).

//vec3 ambient = (kD * diffuse) * ao;
vec3 ambient = diffuse * ao; // <-- my fix

Here you can download the example mod to try it. Pistol is PBR(wrong) and fist is Specular(ok)
https://drive.google.com/file/d/1Ukrw9B ... drive_link