There is no wrong in buying and listening to a cassette recorder if the person buys it to record or listen to recitation of the Qur'an, lectures or religious speeches or the like. However, if the person buys it to listen to unlawful material such as songs or trivial speeches, it is unlawful to buy it and listening to it will also be unlawful. (Part No. 13; Page No. 44)
May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.