Using Audition as Premiere audio editor, not using optimal CPU power

I use Audition as my Premiere editor. I think, my audition can not using my CPU power optimally.

Applying noise reduction and hard limiter in effect rack is really slowly. It just used 12% of my cpu.

This will be problem if i'm on hurry situation.

Is it normal?

I think audion should use maximal power of my cpu so it can work much faster. Thanks

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