Adding alpha channel material layer break the roughness channel

Hello guys i am having this problem UE5 masks

i am using layer materials with RGBA maks but alpha channel breaks the roughness channel

I have a problem with the alpha channel. If you kill the alpha channel with this option the problem
stops. no more weird parts in the roughness map , i suspect that leaving that chequer pattern because the alpha channel is being read some kind of transparency created the problem, it’s very weird not being able to use 4 channels of RGBA mask with this issue.
If anyone has any idea how to keep the 4 channels and not get transparency in the textures please help.
i am using RGBA mask through material functions anyone have any idea

not sure if I am posting in the right place to have an answer

Looks like there is a bug between the engine reading transparency and a pattern coming from the alpha textures.
Is there a way to make it like black and white to be able to use the mask
The solution it’s somehow unreal: don’t disappear the texture with chequer pattern behind and don’t read as transparent instead just read alpha channel black and white like any other channel.
Does anyone have any idea how to do that ?