Question: Is it allowed to play a tape recorder to listen to the Quran before sleeping and it continues to play after one sleeps?
Answer: “There is no harm in listening to the Quran; however, if sleep overcomes him then there is no harm upon him. As for him deliberately leaving it to play throughout the night, then this action does not have evidence for it. Leaving [such an action] is more cautious”.
Faisal Ibn Abdul Qaadir Ibn Hassan