There’s a small app in F-Droid called Speaker www.f-droid.org/en/…/dev.danjackson.speaker/(If you’re not familiar with F-Droid, go down to download the apk, not the big blue download button).
The app outputs noise when a Bluetooth device is connected to stop it from going to sleep. Maybe it’ll help, just keep in mind it will also run down the headphones battery because they will be always active.
I have set volume to 3 so the noise is below the noise level of my speaker.
Another option is go back to enabling absolute volume, and use the app Bluetooth Audio Connect Widget from Gplay. Among other things it can set the volume for a BT device upon its connection.
I use both of these at the same time + GreenTooth from F-Droid for delayed turning off of BT after a device disconnects.
Ed: Don’t downvote me, I’m right. These are both common problems with crappy BT audio devices. With an Android phone you have at least some chance to use it reasonably.
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