Is it permissible to use a musical instrument that produces the sound of a duff (tambourine) in chanting, and is it permissible to replace it with a real duff, and is the participation of chanters with these (performers) considered a sin, and is the earnings from this chanting unlawful?

The use of music, musical instruments, rhythms, and similar sound effects is prohibited, with the exception of the duff (tambourine). This concession is restricted to the genuine duff, and it is not permissible to use another musical instrument under the pretext that it produces a sound similar to that of the duff. Furthermore, the duff for men is a matter of scholarly disagreement, with the preponderant opinion being its prohibition. If you recite nasheeds (Islamic songs) while your companion plays the duff or other musical instruments, you share in the sin. If the nasheed contains beneficial or permissible words and is free from the use of musical instruments and the duff, there is no harm in earning from it. However, if it includes anything prohibited, then the earnings corresponding to that prohibited element are forbidden.