Sounds don't play on Mac Safari + bluetooth headphones + google hangouts

[ericrosenbaum]

This is related to scratchfoundation/scratch-gui#5524

On Mac Safari, if you're using bluetooth headphones, you have a google hangout running that is accessing your microphone, the blocks that play sounds do not work. The "play sound until done" block also stays highlighted forever.

To repro:

1. turn on bluetooth headphones

• On Mac Chrome:

2. Start or enter a google hangout with microphone enabled. The preview screen (before you have joined the hangout) works- it accesses your microphone and shows a little green audio indicator in the bottom left.

• On mac Safari:

3. reload Scratch site and create a new project
4. click on "start sound meow" block. No sound plays.
5. click on the "play sound meow until done block". No sound plays, and the highlight stays on.

Sometimes it starts working after I reload the page, but I still see the sound editor crash (scratchfoundation/scratch-gui#5524) in that case.

Operating System and Browser

Mac OS 10.15.2 Safari 13.0.4
also: Mac OS 10.14.5 Safari 12.1.1

[AmazingMech2418]

Maybe is this an issue with accessing the audio drivers in Safari? Given how specific the bug is to using a Mac, running Scratch on Safari, and running the Google Hangouts on Chrome, it seems like it might be a bug of an external application, such as Safari or even MacOS in general. If someone can reproduce this on another OS, that could make it a Scratch bug, but the audio not playing seems like it might be an issue with the audio controls on the device, which might be caused by one application locking audio out for the other, or issues with the Bluetooth connection being shared between applications.