Hello, I'm having a bit of a problem as I work on my first ever zombies map - I haven't added anything custom but I've noticed that some textures in the map are tinted red for some reason; and before you ask yes I have a reflection probe and light grid volume aswell as a skybox with the worldspawn values copy/pasted from Der Riese.
 
I'm honestly stumped as to what causes this issue as I can't find anyone experiencing this on this site, if anyone can help it'd be greatly appreciated! Below are pictures for reference.
 

 
 

 

 

I have this issue too but what sometimes happens is when you continue on your map (or recompile idk) it seems to fix it sometimes
 
Sry this is all i can give you on the way maybe someone konws what to do against it
 
-Smol

You need to place reflection_probe 's in all the rooms you have.
 
Open radiant, right mouse click on the grid view to see the probe.

You need to place reflection_probe 's in all the rooms you have.
 
Open radiant, right mouse click on the grid view to see the probe.

This worked but since I only had one room I'll elaborate for anyone who might see this thread in the future:  
You need to place reflection probes anywhere the first one doesn't reach - even if it's in the same room. Whether it be under something or behind something.