Is it forbidden to remain silent regarding counseling the owners of stores that sell music tapes and musical instruments?

It is not permissible for a Muslim to sell anything that is used for unlawful purposes, because Allah, the Most High, says: "And cooperate in righteousness and piety, but do not cooperate in sin and aggression." And because the Prophet, peace and blessings be upon him, said: "Indeed, when Allah Almighty forbids a thing, He also forbids its price." And it is obligatory upon a Muslim to denounce evil through advice and warning, to the best of their ability.