How to reproduce:
1. Open the “bug-audiomixer-destroyed.zip“ project
2. Open the Addressables Groups window (Window > Asset Management > Addressables > Groups)
3. Select "Use Existing Build" in "Play Mode Script" in the Addressables Groups window
4. Build the Addressables (Build > New Build > Default BuildScript)
5. Open the “AudioScene“ Scene
6. Enter Play Mode
7. Observe the audio volume in the Game view
8. Click the "Unload Audio Mixer Group" button in the Game view
9. Observe the audio volume in the Game view

Expected result: The audio continues playing at the previously observed volume
Actual result: The audio starts playing at full volume

Reproducible in: 2021.3.45f1, 2022.3.51f1, 6000.0.24f1

Reproduced on: Windows 11 Pro (23H2), macOS 14.6.1 (M1) (by the reporter)
Not reproduced on: No other environment tested