f5ae7c75_r_Audio___Download___PCMag_com__What_To_Do_With_It
[The Problem] Subsonic noise like traffic, foot-taps, or the rumble of a tape-transport [The Tool for the Job] High-pass filter [What To Do With It] 
Set the filter to remove sound below 20Hz. Use a steep cut-off to make sure no noise leaks through.
Online Extra: After the Noise is Gone - Clean Your Audio - Download | PCMag.com
What To Do With It