Media Stream Not Released on Closing

[rmollenkamp]

• I'm submitting a ...
  [X] bug report
  [ ] feature request
  [ ] question about the decisions made in the repository
  [ ] question about how to use this project

• Summary

• When using this package as it exists on NPM, when calling close(), the media streams that were requested are not closed, and the application continues to use the provided audio source.

• Other information (e.g. detailed explanation, stack traces, related issues, suggestions how to fix, links for us to have context, eg. StackOverflow, personal fork, etc.)