Had the same noise problem. Based on earlier answers, I opened up the unit but found no problem with the speaker, nor its wiring. Noticed the battery quite weak. After charging, then the noise disappeared.
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Had the same noise problem. Based on earlier answers, I opened up the unit but found no problem with the speaker, nor its wiring. Noticed the battery quite weak. After charging, the noise disappeared.
Had the same noise problem. Based on earlier answers, I opened up the unit but found no problem with the speaker, nor its wiring. Noticed the battery quite weak. After charging, then the noise disappeared.
Conclusion: the battery was not properly charged.