First check the audio source, does the noise disappear when selecting another input source (e.g. USB stick/WiFi streaming/Bluetooth/CD or similar) Check the gain settings of the amplifier/radio. Does the error occur in certain volume ranges? Is the loudspeaker touching the cover/standing on? Was the loudspeaker operated with too high load for a long time? If the error cannot be corrected, the loudspeaker must be sent in for inspection. Based on the error pattern, a possible warranty case can be determined. Loudspeakers outside the legal warranty periods can also be sent in for inspection for a fee.
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