WhatsApp tests voice message playback speeds on mobile
WhatsApp is currently working on offering different playback speeds for voice messages. According to WABetaInfo, the app version with this feature is still in the works, but it's expected to show up in a future build. It will allow you to speed up messages at 1.5x or 2.0x speed. Since this is just a preview, we don't know yet what you'll need to do to access this option. But it's in development for both Android and iOS.