Resonance Audio ambisonic decoder does not work properly with Audio mixer controls

1. What happened:
When Resonance Audio ambisonic decoder is used and hooked to an audio mixer control, the user cannot control mix volume of the Ambisonic source via the slider, and the mute channel button either doesn't work at all or can experience delays up to 5 seconds before the channel is muted.

2. How we can reproduce it using the example you attached:

1. Ensure that Edit->Project Settings->Audio (Spatializer Plugin and Ambisonic Decoder Plugin) are both set to Resonance Audio.
2. Ensure that the Cube has an Audio Source attached using the FOA_speech_ambiX.wav and that it is set to loop and Play On Awake.
3. Ensure that the FOA_speech_ambiX.wav asset has the Ambisonic check box checked and that the Apply button was pressed to apply the change. To access these settings, left click on the sound asset.
4. Ensure that an audio mixer group has been created under the master sound mixer, that the cube Audio source Output has been assigned to the audio mixer group, and that Resonance Audio has been added to the audio group (should be under the basic Attenuation component).
5. Ensure that Spatialize is not checked on the Audio Source.
6. Play the scene with the Audio Mixer window open.
7. Toggle the M button on the Audio Mixer channel,
8. Observe that the channel sometimes doesn't mute at all, and other times experiences a very long delay before being muted.
9. Observe that the Audio Mixer channel attenuation slider has no effect on the audio level, even though in the Inspector window it shows the audio level being reduced to 0.