Yup, been there too with wedding coordinators ... people who know nothing whatsoever about music yet try to tell me how to play the organ.
On one occasion, at a wedding rehearsal in my own church, a visiting wedding coordinator (who was not a musician, let alone an organist or pianist) came over to me and said "can't you play that processional (Trumpet Voluntary) quieter?". I refused ... she said, "well, we'll see about that!" I said "see about what?" She retorted, "well if you don't do as I say, then we will get another organist!" I said "fine ... you do just that.", and walked out.
The bride and brides family begged me to come back ... I said "only if that barracuda leaves me alone (within earshot of the coordinator) ... !" After the wedding, she said "well, it should have been quieter!" Moron. :lol: