On restarting from Virtualizing, any parameters set previously on a MetaSound are ignored and the MetaSound restarts with the default values. This does not behave this way with Sound Cues, in which the last value set on the parameter is maintained even after restart.
On MetaSounds, if the sound is set to Play When Silent, the parameters are maintained to the last set value. Issue only occurs on Restart.
1) Launch AudioQA or any project that has the MetaSound plugin enabled
2) Create a MetaSound Source *and *remove the One-Shot Interface. Create a simple MetaSound that takes in an Input *that can be set in *Blueprint. For example:
3) Create a Blueprint and add an Audio Component. Set the Audio Component to your MetaSound Source. Add a call to set a Parameter (make sure the name matches the name of the Input node). Ex:
4) Select the Audio Component in the BluePrint and select Override Attenuation
5) Add the Blueprint to the Default Level and PIE. Observe the sound is effected by your parameter setting
6) Open the console and enter au.3dVisualize.Enabled 1 (this makes it easier to see the state of the sound)
7) Move the camera away from the sound until it becomes* Virtual*
8) Approach the sound again
The sound will still be effected by the value that was set on the parameter
The sound restarts with it's default values
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-164898 in the post.