The effects of flow on the acoustic behavior of metamaterials can be very significant and possibly destructive. To avoid these detrimental effects, it would be a good idea to have a "magic layer" that allows acoustics to pass through while suppressing the sound-flow interactions. A possible realization of this layer based on Kevlar fabric is tested in this paper. It is shown that, in the presence of Kevlar, flow-sound interactions that can lead to acoustic amplification and whistling phenomena are avoided. Thus, Kevlar will permit liner designs including large slits. However, it adds large acoustic losses, which limits interesting resonance effects in applications.