Normal speed is achieved with “mpv: set speed 1”
FWIW, I’ve been using (with some caveats) the following speed controls in my keyboard.json going back to PMP, which was also MPV-based:
//Speed Controls "N": { "short": "mpv:set speed 0.5", "long": "mpv:set speed 0.25" }, "M": { "short": "mpv:set speed 2", "long": "mpv:set speed 4" }, "Alt\\+1|Ctrl\\+1": "mpv: set speed 1", "Alt\\+2": "mpv: set speed 0.5", "Alt\\+3": "mpv: set speed 0.25", "Alt\\+4": "mpv: set speed 0.125", "Ctrl\\+2": "mpv: set speed 2", "Ctrl\\+3": "mpv: set speed 4", "Ctrl\\+4": "mpv: set speed 8",
