There is nothing wrong with a Muslim listening to Qur’aan before he sleeps, or listening to a lecture or anything permissible. Indeed it is narrated in the saheeh Sunnah that among the adhkaar to be recited before going to sleep are some du’aa’s and verses and soorahs from the Qur’aan.
Chapter: Seeking refuge with Allaah and reciting Qur’aan when going to sleep
It was narrated from ‘Aa’ishah (may Allaah be pleased with her) that when the Messenger of Allaah (peace and blessings of Allaah be upon him) went to bed, he would blow into his hands and recite the Mu’awwadhaat, and wipe his body with them.
Narrated by al-Bukhaari, 5960.
It was narrated that Abu Hurayrah (may Allaah be pleased with him) said: The Messenger of Allaah (peace and blessings of Allaah be upon him) appointed me to guard the zakaah of Ramadaan, and someone came and started to rummage in the food. I took hold of him and said: “I am going to take you to the Messenger of Allaah (peace and blessings of Allaah be upon him)”… And he said: “When you go to your bed, recite Aayat al-Kursi, and you will have ongoing protection from Allaah and no devil will come near you until morning comes.” The Prophet (peace and blessings of Allaah be upon him) said: “He spoke the truth even though he is a liar; that was a devil.”
Narrated by al-Bukhaari, 3101.
Listening to Qur’aan before going to sleep and after, during Ramadaan and at other times, instills tranquility in the heart and helps one relax. Allaah says (interpretation of the meaning):
“verily, in the remembrance of Allaah do hearts find rest”
And Allaah knows best.