If you have serious issues of playing music from your Macbook Pro through Bose bluetooth portable speakers, you may try the following and see if the issue is fixed. I fixed mine which lasted over one month.
Restart the sound controller
- Go to Applications>Utilities and double-click on Activity Monitor to launch it.
- In the search bar, type 'coreaudiod’ to locate the Core Audio controller.
- Click on coreaudiod, then click ‘X’ in the tool bar to quit it.
- Coreaudiod will restart.
Source: https://macpaw.com/how-to/fix-sound-on-mac
