Unwrap with ZBrush to Substance painter adds weird dark squares


Hey guys, I recently started to learn Substance painter. The problem I have now comes from ZBrush I recon. Before I export my model I use the ZBrush UV unwrap option under Plugins.

I then import the model into my Substance painter and everything looks fine.

When I am done, I import the model into 3ds Max, I add the textures to it and it all looks good except for a little “thing” that I noticed. I am not sure what to call it, but check the picture please.

There are some dark(er) squares on the model that I did not paint myself. I think it has to do with the UV mapping maybe?

Does anyone know how I can fix this? or can someone maybe explain to me what the perfect way would be to UV unwrap the right way? ZBrush does it automatically at the moment for me.

Best regards