Greetings ,
I generally listen to Librivox recordings using smplayer :
https://www.portablefreeware.com/index.php?id=1358
and sometimes I want to slow down the recording .
Here is a tip how to do that :
https://www.portablefreeware.com/forums/viewtopic.php?p=105060#p105060
One option is to mess with the global speed setting. Open Options -> Preferences -> Advanced -> MPlayer/mpv, and add --speed=0.9 (or any speed you like) to the Options field. You can them remove it once you've listened through the whole playlist .
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