Singing a song in a dream could have different meanings as per Islam as explained below.
1- According to Ibn Sirin رحمة الله عليه the greatest dream interpreter of Islam, singing in a dream is an indecent act and trial.
2- Singing with musical instruments such as drums and guitar in a dream means that the trials would be intense.
3- Listening to a song in a dream reflects listening to the vulgar talk.
4- According to Ibrahim Karmani رحمة الله عليه singing in the public reflects that the rich people will get humiliated and the poor will face sorrow.
5- Many dream interpretations reflect that singing in the dream or listening to the song in the dream is because for the following reasons;
- Vulgar talk.
- Sadness and sorrows.
- Knowledge and wisdom.