Stuff yer drains – With Chord Company's GroundARAY [£550], you can. These parallel noise traps are available in six terminations including USB A, HDMI, RJ45, BNC, RCA and XLR. They plug into unused connectors and present a very low-impedance high-bandwidth route for HF noise in the circuit to pool into them where they dissipate as heat. Here is a YouTube video. The insides of these thin cylinders fill with undisclosed UHF noise-absorptive material to exceed standard shorting plugs.