These headphones have a massive marriage - by itself, in the charging case, one earphone is discharged to zero (the right one, as a rule). The fact that the problem is not a single one is indicated by the number of queries on this topic in search engines. To resurrect a dead ear, you will have to do dances with a tambourine - throw the earpiece on the charging contacts 50 times until it receives a minimum charge, comes to life and starts charging. I myself encountered this problem, I do not recommend these headphones,
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