AudioReplace
AudioReplace[audio,{t1,t2}->new] replaces the audio signal between t1 and t2 with the new signal new.
AudioReplace[audio,{{t11,t12},…}->new] replaces multiple intervals with the same audio new.
AudioReplace[audio,{{t11,t12}->new1,…}] replaces multiple intervals.
AudioReplace[audio,{t1,t2}->new,fitting] uses the specified fitting method.
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