Audio: Using audio bus effect equalizer after playing a sound leads to a longer high cpu load period

[EadraxOffice]

Godot version: Godot engine V3.2.1.stable X64

OS/device including version: Windows7 X64 Build 7601 SP1/ Linux X64 (custom build)

Issue description:

Playing a sound with a audiostreamplayer or a audiostreamplayer2D instance on a audio bus (cascacde) with enabled equalizer effect will lead to a high cpu load and frame timeouts after the sound play was finished. On larger godot project this results in a delay up to 10.000 msec or more where you also have load from GPU usage or gdscript usage. I have tested this behavior on Linux and on Windows with a small sample project.
Same behavior here too. In one of my sample project run (under Windows) the delay was just 22ms over a longer period but it shows the issue as well.

Disabling the equalizer (EQ21) effect in each audio bus by gdscript is solving the cpu usage problem immediately.

Steps to reproduce:

• Place a audiostreamplayer in a node2d
• Add audio busses and EQ21 effect like in the picture below:

• Set audiostreamplayer instance in the inspector to Bus "EQ2"
• Start the godot editor debugger tab "Profile" and hit start.
• Enable sub Master Eq21 and other audio bus effect for the measure
• Play a short sample sound and look what happens after sound play has finished.

equalizer_test.zip

Minimal reproduction project: