AirPods Static/Hissing Noise when nothing is playing.

why does my AirPods has a static/hissing noise when its in my ear and nothing is playing on it, the noise can be heard when the volume of a music or a video is low but it can’t be heard when there is a high volume music because the noise is drowned by the high volume music, but when the volume of a music is low or there is no playing on the AirPods u will hear the static/hissing noise, i’m trying my best to ignore it but its driving me crazy especially i can hear the noise when the volume is low and the only problem that is pushing me back from replacing it is that the sound can only be heard in a quiet room but in a mall u cant hear it so its possible it can’t be heard in a mall and end up getting it not be replaced because it cant be heard in a mall since the noise is not so loud but i want an AirPod that is free of any noise when its in your ears and nothing is playing should i replace it??