How to Fix Subwoofer Hum with No Input - BoomSpeaker
How to Fix or Eliminate Subwoofer Hum
Bah! The Subwoofer Hum Bug, and How to Stop It-- Blue Jeans Cable
Skyjuice: Fixing Humming Noise for Subwoofers
Why does my home subwoofer hum when power and RCA is connected? If I disconnect the RCA, it stops. How do I fix it? - Quora
Thank you r/diyaudio. Your advice to change out the capacitors got my friend's subwoofer working again with no loud humming noise. I can't wait to see his reaction when he gets to