I often wondered why the Society migrated away from live piano music to the recorded variety. I suspected that those of us who played the piano at the KH would put emotion into our playing, or add some sort of creative twist to the music, which was too close to displaying an "independent spirit". If the music is played from a recording, then the WT has control of the mood of the music. Of course, all of this was done under the guise of "unity of the brotherhood."
BTW - we attended a church in Wenatchee, WA. We were surprised to find a Kingdom Melody in their hymnal - We Thank You Jehovah. Don't know where they got it, who had it first, but were rather surprised because we thought JW songs were exclusive to JWs.