Strange async behavior for play sound on hardware

If you call the synchronous play sound immediately after a call to the asynchronous play sound, the program waits for the first to complete but not the second. In this program:

When you press the B button, the icon shows after the first sound finishes instead of the second. This might be a DAL issue, but i'm not 100% sure

To Reproduce
Steps to reproduce the behavior:

1. Download this program onto a microbit: https://makecode.microbit.org/_Az5FYmUtsDL9
2. Press the A button, note the correct behavior
3. Press the B button, note that the icon shows after the first (async) sound stops playing when it should only show after the second sound finishes

Expected behavior

Should wait until both sounds finish