Perhaps LPCnet may be of use to you. If is a neural net for generating speech based on google's research. The demonstrate using it to intelligently slow down or

Perhaps LPCnet may be of use to you. If is a neural net for generating speech based on google's research. The demonstrate using it to intelligently slow down or speed up audio. perhaps you will find 3x audio more natural with it. maybe a smart accelerator could be made that speeds up quiet parts more. https://people.xiph.org/~jm/demo/lpcnet/ https://people.xiph.org/~jm/demo/lpcnet/