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speakers humming buzzing when plugged into laptop charger

Ask By Megan F.1,471 views

theres a constant hum from my speakers only when my laptop is charging. unplug the charger and its gone. so annoying

Brand
Edifier
Model
R1280T
Connection
Wired 3.5mm Jack
System
Windows 10/11
Browser
Chrome 130
Sample Rate
48 kHz
Output Channels
2 channels
Tool used in this discussionSpeaker TestStereo balance, phase and polarity across bass, mids and treble
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Short Answer

A hum that only appears while charging is a ground loop through the power supply. A USB audio adapter or a ground loop isolator on the audio cable usually removes it.

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Lars Neumann
Lars NeumannAudio Team
Electroacoustics Engineer · 6+ years experience · Answered Oct 9, 2026

This is a classic ground loop. When the laptop charger and the speakers both connect to mains power, a small voltage difference between their grounds travels through the audio cable and shows up as a steady 50 or 60 Hz hum.

The hum disappearing on battery confirms it. The cure is to break the loop, not to replace the speakers.

Step By Step Fix
  1. Plug the laptop charger and the speakers into the same power strip
  2. Try a different wall outlet for the charger
  3. Connect the speakers through a USB audio adapter instead of the headphone jack
  4. Add a ground loop isolator between the laptop and the speakers if you want to keep the jack
  5. Play the Speaker Test afterwards to check that the left and right sides are clean

Checked by Amit Malhotra on . How we verify answers

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Community Replies 4

  • Alyssa PerryCommunity Member

    ground loop. i got a cheap ground loop isolator for like 10 bucks and the hum was gone

  • Cody ReynoldsCommunity Member

    try unplugging the charger and see if it stops, if it does its the charger noise

  • Megan FosterCommunity Member

    stops when i unplug it so ill grab the isolator. thanks

  • Amelia WoodCommunity Member

    The ground loop isolator worked on mine too. I bought a small one online and the hum was gone straight away.

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Lars Neumann
Written and tested by

Lars Neumann

Electroacoustics Engineer at Sound Test

Lars Neumann is the Electroacoustics Engineer on the Sound Tester Audio Team. Conducts strict transducer distortion testing, frequency response matching, and ambient room noise profiling. Active in international acoustics engineering forums and Mastodon. Based in Germany. On Sound Tester he answers hum, noise and distortion discussions, and explains how room and wiring affect what you hear.

Transducer distortionfrequency responseroom noise
  • 5 answers on Sound Test
  • 6+ years experience
  • Reviewed by Amit Malhotra

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