When the speakers hum, buzz, or crackle, that means there is interference coming from somewhere, and you need to find the source. As you are trying the following suggestions, please note which one(s) solve the problem in order to identify the source. When you have identified the source, please contact Technical Support.
Unplug the audio cable and make sure it’s plugged in securely when you reconnect it.
Plug the audio cable into a different audio port.
If you are connected to a laptop, unplug the power cable and use it on battery.
Test the sound at various levels to ensure it is not an issue related to volume.
Try a different (known working) audio cable.
Try a different source.
If you’re connected through a wallbox, then try connecting directly to the amplifier.
Do you have the same interference when the sound is coming from headphones?