Air bars, stones, bubblers, etc. have no place in a SW
. As the bubble burst at the surface, they send salt spray upward, coating everything in proximity with precipitated salt. Everyone gets salt creep to some extent but the bubbler will increase yours many times over. At least thats been my experience. I had one too (they do look cool) but took it out after a short time.
The noise you hear is the pump cavitating on air which can be bad if it is prolonged but a little here and there probably does no harm. I vote for removing the bubbler but it's up to you.