What is the ruling on quietly reciting the Qur'an in a low voice when hearing loud music in public places?

Singing accompanied by music is forbidden, and it is obligatory to condemn this evil to the best of one's ability. There is no harm in reciting the Quran silently in this situation, as it is a way of enlivening moments of heedlessness with the remembrance of Allah, similar to engaging in dhikr in the marketplace and the like.