Symptoms
- Hum or buzz appears only when a phone or device is charging nearby
- Noise changes pitch or intensity based on charger brand
- Noise disappears when the charger is unplugged
- No noise when playing audio through a different input
Likely causes
- CommonCheap or poorly shielded USB charger causing electrical interferenceLow-quality switching power supplies can emit noise that couples into nearby audio cables.
- CommonGround loop introduced by the charging device sharing power circuits with the audio systemA phone or laptop charging while also connected to the audio system (e.g., via USB or aux) can create a ground loop.
- PossibleUSB cable running parallel to audio cablesData and power cables running alongside audio cables can induce noise through electromagnetic coupling.
- PossibleFaulty or degrading USB chargerA charger nearing failure can emit more electrical noise than a healthy one.
- Less commonSoundbar's internal power supply sensitivity to nearby interferenceSome units are simply more susceptible to nearby electrical noise than others.
What to do
- Unplug the USB charger and see if the buzzing disappears immediately, confirming the charger is the source.
- Try a different, higher-quality charger or the original manufacturer's charger for that device.
- Move the charger and its cable away from the soundbar and any audio cables.
- If the charging device is also connected to the audio system (e.g., playing music while charging), try charging it separately, not through the audio path.
- Plug the charger into a different outlet or power strip than the soundbar.
- If using a USB hub or multi-port charger, test each device individually to identify the specific noisy one.
When to call a pro
This is very rarely a soundbar hardware issue; if buzzing continues without any charger connected, then technical service may be needed.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.