Unknown audio samples take 1 GB

Here is my problem: I have a big scene with many audio sources, but actually a very small amount of audio clips. Most clips are set to "Stream from disk", and others (very short ones) to "Compressed in memory". However, Unity somehow takes up to 1 GB (!) with the audio subsystem. People with <= 2 GB RAM are complaining that they can't play the game. The game itself, without counting the audio system, takes around 800 MB or less.

I attached screenshot from profiler.

How can it happen? I double...

Unknown audio samples take 1 GB