In 2011 Superconductors.ORG discovered that background thermal noise in a bulk material that contains a low-volume-fraction (VF) superconductor diminishes as it cools below Tc. Now, an examination of the plots of many suspected room temperature superconductors reveals there is a quantifiable drop in noise in them as well.
Joe Eck provided sample plots from seven different compounds, all of which are thought to contain room temperature superconductors. They all produced sharp diamagnetic, resistive and/or specific heat changes during earlier testing. A visible reduction in background noise has been found below Tc in all of them.