An audio source that goes through a mixer reverb effect gets cut off prematurely.

Reproduction Steps:
1. Build & Run the attached project for PC
2. Press left-click to trigger the audio source to play
3. Listen to the effect for a short while, it will echo away over time
4. Press right-click to switch to a scene using a mixer for reverb
5. Press left-click to trigger the audio source to play
6. The reverb effect will suddenly cut off

Expected Result:
The reverberation effect should continue until the audio source has become sufficiently quiet enough that stopping it doesn't result in a noticable cutoff of the sound.

Note that this doesn't happen in the Editor, only in a build, and also that a workaround is available by disabling the Auto Mixer Suspend option on the mixer.