Audio PostLateUpdate.UpdateAudio -> AudioManager.Update takes 40ms on empty scene

Up to 100ms, actually, didn't want to sound like clickbait.
Doesn't matter if I have AudioSource in the scene. CPU - Core i-5 8600K. Unity version is 2017.4.1f1.
Any ideas?

 

I'm almost positive I know what is causing this for you so let me ask - how many audio mixers/controller groups do you have in the project? I have discovered a huge issue with Unity and audio mixers in that if you have loads of them (even inactive with no audiosources) it will cause a huge drain on the CPU.

I found this feedback post: https://feedback.unity3d.com/suggestions/mixer-performance-issue

And I have since logged it as a bug with Unity too so it get's looked at.

I recently joined a game where we have over 1,000 mixers already and have been trying to solve our 50% CPU usage on audio. When I just deleted 80% of the mixers down to like 200 the performance was exponentially better. From 30ms processing delays down to 0.5 ms. It seems like there is a critical number of mixers somewhere around 3-500 or so where the performance completely tanks.

I'd recommend going with as few mixers as you can! Hope this helps!

 

I am getting 1000ms spikes on AudioManager.Update..... with ZERO mixers. How did you profile this? Or was it just a guess at mixers and you went from there?