At 96kHz sampling rate you have filters that cover an audio band from roughly 0-48,000hz.

At 192kHz sampling rate you have filters that cover an audio band from roughly 0-96,000hz.

The workload on the filter has doubled.

At 96kHz you have X number of samples in Y amount of time.
At 192kHz you have X number of samples in Y/2 amount of time. Or 2X in Y time.

So twice the workload in 1/2 the time.

Shawn

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