AUSounds AU-STREAM HYBRID Benutzerhandbücher Seite 7

CHARGING
Battery life
Please charge for 1 hour prior to first use. In Bluetooth mode only,
a single play can last up to 9 hours, and the total battery life can
reach 25 hours with charging case.
Earbuds
Put the earbuds in the charging case and they will automatically
shut down and enter the charging state.
Charging case
When the battery power for the case is completely depleted,
remove the earbuds from the case and allow the case to charge for
15 minutes before charging the earbuds within the case.