This Rage Against the Machine video from 1992 is a musical artifact along the same lines, though not quite as anarchronistic, as the 1985 video of 17 year old LL Cool J live in Maine. This show is at Zed’s Record’s in Long Beach and is almost exactly before their first album came out. Fast forward to about 25:30 when the PA goes out and Zach de la Rocha just keeps singing anyway, the vocals caught super quietly through the camera’s microphones. CowProd, the Youtube uploader (and cameraman) has another couple older RATM videos, including this one from a few weeks earlier.
Thanks, Alex.