Multiple BIG/Subgroup implementation on Android OS

[ble_4life]

We managed to get the nrf5430 Audio DK broadcast source application running with two subgroups each containing at least one mono stream and custom metadata about the streams.

On the opposite another nrf5430 Audio DK could run a broadcast sink and toggle between both streams via a button.

The problem was when trying to receive the streams via a Samsung Galaxy A55 5G running Android 14 and Samsung Galaxy Buds Pro 2. It was displaying both streams separately in the selection menu correctly. When selecting the first stream it was playing back the audio correctly. When selecting the second stream, it simply jumps back to the first one with a certain amount of silence and continues playing back the first stream.

We currently waiting for the Android 15 release, to test the behavior again.

Our questions are:

(1) do you have information about the status of the BLE Audio implementation on the smartphone OS side, especially in regards the broadcast functionality?

(2) do you know additional ways to ensure we're on the right path (not breaking anything regarding the BLE standard) - except from expensive BLE sniffers or PTS?

Best,

Alex

[dejans]

Hi Alex,

Your questions are quite general.

(1) do you have information about the status of the BLE Audio implementation on the smartphone OS side, especially in regards the broadcast functionality?

Do you have any specific smartphone OS in mind? This question seems more suited for smartphone manufacturer/vendor. Have you tried to contact them?

(2) do you know additional ways to ensure we're on the right path (not breaking anything regarding the BLE standard) - except from expensive BLE sniffers or PTS?

Is there anything specific that concerns you? Can you elaborate on "additional ways"? What do you consider to be first/primary way?

Best regards,
Dejan

[ble_4life]

dejans said:

Do you have any specific smartphone OS in mind? This question seems more suited for smartphone manufacturer/vendor. Have you tried to contact them?

As we currently work with Android, I would focus on that OS. But iOS as a major used OS is also in our interest. Of course it is rather a topic for the smartphone manufacturers. But I had a chat with one of your field application engineers on a Nordic workshop about that topic and he mentioned some known issues with the selection of audio streams on Android. I've hoped to get some details on that here on devzone on his advice.
I've created a developer ticket on Samsung, but the first stage support didn't understood my problem and closed the ticket.

dejans said:

Is there anything specific that concerns you? Can you elaborate on "additional ways"? What do you consider to be first/primary way?

So I want to ensure I follow the standard regarding the creation of subgroups, advertising them with the correct metadata and their ISO streams. In other words I want to go sure the Nordic/Zephyr implementation is not fault, but eventually it's the Android OS.
I did checked the list of current available test cases for the BAP profile and the only one I found which goes in that direction is about a "Multi BIG configuration" (it's the BAP/BSRC/SCC/BV-38-C). Not subgroups or streams. Based on that missing test cases I assume the market is not "ripe" yet for the multi-subgroup configuration?