Editor Crash on changing speaker when audio track is playing in timeline

Steps to Reproduce
1. Create a project.
2. Get some audio clips from old projects or use new.
3. Create Cube.
4. Open timeline window and select cube and click on create and save the file.
5. Add audio track and assign the sound
6. Hit the play button and change the speaker to internal to external.

License Type: Pro & Free

Occurring with: 2018.1.0b7, 2018.1.0b6, 2018.1.0b5, 2018.1.0b4, 2018.1.0b3, 2018.1.0b2, 2018.1.0b1, 2018.1.0a1, 2017.3.0f3, 2017.2.0f3, 2017.1.0f3

Reproducible on: Mac mini only (OSX Version 10.12 and 10.13).

Note:- This is not occurring on Mac book Pro(Retina).

Log result :
Default audio device was changed, but the audio system failed to initialize it. Attempting to reset the sound system.