Double flush: little distoRtion

[Gledison]

Hey guys!
Just tested my double flush temporarely using a 10k log for the intensity! Well, im very happy with it! The only thing that il not sure if its ok is: when i adjust the BAL to full, i get s slight distortion( crunch). I thought that the balance its only to mix between the wet and dry signal, something wrong here or is this normal?
Cheers