Years ago (early 1980's), JVC made a VCR that had 2x playback with audio.
Granted, the audio wasn't perfect, but it was at 2x speed without raising
the pitch of the audio. It used an analog bucket brigade IC to accomplish
this.

I'm sure it's possible to do digitally/programmatically with a wave file,
but I'm not sure just how or what algorithm to use.

BTW, I've seen some AV clips online that allow you to view them at 1.5x

Any experience or insight appreciated.

Tom