UserAgent: Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/54.0.2840.71 Safari/537.36

Steps to reproduce the problem:
1. Run the Select sources & outputs sample (https://webrtc.github.io/samples/src/content/devices/input-output/), running in Chrome 54.0.2840.71 m on Windows 10 64bit (build 14951) 
2. Seems to enumerate the audio output devices correctly, but is unable to output to one specific device, namely a Plantronics BT300M Headset.

What is the expected behavior?
In Windows you have the option of defining a default output device AND a communication output device. The Plantronics headset is set as the Communication output device and the above sample DOES correctly output audio if the "Communications" device is selected in the dropdown, but not if the actual Plantronics device itself is selected.

What went wrong?
In fact, audio is actually heard through a completely different device, in my case this so happens to be the main speakers (or the default audio device).

Did this work before? No 

Chrome version: 54.0.2840.71  Channel: stable
OS Version: 10.0
Flash Version: Shockwave Flash 23.0 r0

Chrome 54.0.2840.71 m on Windows 10 64bit (build 14951) 
Reported to https://bugs.chromium.org/p/webrtc/issues/detail?id=6605#c2, they suggested posting here.