Expoel @ 04.24.19, 16:22
that is, only the i20 is turned off by closing the lid, and all the other headphones are not turned off?
You misunderstood. Headphones with a charged case, if they touch the contacts of the case, immediately disconnect from the phone and begin to charge, the cover is open or not, it does not matter. And they will connect to the phone while in the case only if the case is completely discharged, otherwise the headphones will turn on only if they are pulled out of the case (open the headphone and case contacts).