Dictation Example failure on app close

[marlenaklein-msft]

This issue has been migrated a new MRTK repository, and the status of this issue will now be tracked at the following location:

• Dictation Example failure on app close MixedRealityToolkit/MixedRealityToolkit-Unity#59

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Describe the bug

After closing and then opening (not fully relaunching) the dictation example scene, dictation stops working.

To reproduce

Steps to reproduce the behavior:

1. Build the dictation example scene.
2. Start dictation, then either stop dictation or leave it running. Both reproduce the failure.
3. Exit to home.
4. Open the app again.
5. Try to start dictation again.