If your Stockwell II speaker is emitting a crackling sound, the likely cause is that the amplifier is clipping as it has run out of output power.
You can troubleshoot by decreasing the volume on your audio source, or lower the volume or bass on the Stockwell II speaker.
If you cannot troubleshoot your product or believe it to be faulty, please click here to submit a request or contact us via the live chat function in the bottom right corner.