Sound from both tablet AND Bluetooth speakers??

[pofadda]

I’ve recently been running a Bluetooth speaker - Duronics SPB2 - from an old Nexus 10 tablet with a custom Oreo ROM and via the Macrodroid automation app. (For what it's worth, the macro was to turn a recording of bird calls on and off each day.)

This setup caused the audio to play through both the Bluetooth speaker and the tablet's speaker. Although the Bluetooth's volume drowned out the tablet's, the need to play the file at full volume - the two volume controls were not connected as they are on my phone - must have an effect on the ageing tablet's battery life.

I'm hoping someone out there has seen this dual-play behaviour before and had a solution to it. I suspect it's a quirk of Macrodroid or its interaction with the Duronics speaker which shows no connection between the two devices' volume controls. From my bit of research, some folk would pay good money to have sound coming from both outputs!

 

[VidJunky]

I believe your post may have gone unanswered due to some confusing issues included in your description of the issue.

You clearly want to the BT device to play the audio at 100%. Typically BT volume control becomes the primary control on a device when one is connected. Is this not the case for you?

Are you able to push the BT volume to max? There are usually safeties built in to prevent the volume from starting off at 100% when an external device that could be a headset is connected. Attempting to push the volume to higher levels results in a warning that must be agreed to or acknowledged before allowing higher levels. Are you seeing this warning? Are you able to push the volume to maximum?

I wouldn't see how the tab's battery status would affect the volume from a BT device even if the tab's power forced it into a power saving mode. I can on the other hand see how it might reduce the tab's volume output as more volume=more work and power saver may try to limit this. Could the reduced volume appearance be due to the tab's reduced output? So when they are working in concert, even if the tab is believed to be less than the BT, the overall sound is dampened.

To further complicate the issue the tab has been rooted. With root there are so many possibilities of issues and setting adjustments that it is often very difficult to pinpoint certain issues. However that also gives opportunities. Have you tried looking for a way to control the volume from setting only available in root? While stock devices are limited by controls within the OS, like volume and processor speed, these settings are usually set to protect the device from harm. Speakers can be pushed too far and might blow. Processors can be pushed too hard and cause overheating or damage. They can do more than the OS will allow, outside of the safety margins.

In your last statement you mention dual play behavior. I have seen and talked about this many times as it is typical behavior for alarms, phone calls and notifications. The sound will often play from both the device and the BT device. I assume this is to be sure the sound is not missed. I haven't seen or heard of it with simple playback or streaming. This could be a result of a defect in the ROM or other intentional settings from the ROM. Perhaps this could be combated by installing a volume control app. There are several volume control apps that break down control over device audio more extensively than the basic controls which might be, Calls, Notifications, Media and Alarms. Perhaps with the use of such an app you could mute the tab while allowing BT to continue to play? While phones are not tabs and I'm running a stock OS I can tell you that I can run my volume down to mute and still play audio through my BT device, and at max levels. I can do this stock without the use of an app. What happens if you mute the tab with the BT connected? Does it also mute the BT volume control?