As a lay preacher and active member of a congregation, I can confirm what you said. However, though the problems almost always start there, they often are unrelated to the music! It seems, at least in my faith tradition, that the members mostly likely to be in the center of any controversy are the most active members, and the most active members are usually in either the Worship and Music Committee and/or the Choir or band. However, though usually it's choir or band practice or else committee meetings when those folks gather together, the things they'll start squabbling over cover the whole gamut of church issues.
When the pastor convinced the Altar Guild to change from using leavened bread over to pita bread for communion, you'd have thought he had nailed 95 theses to the church door! The arguments started in choir practice, but soon spilled over to the entire congregation.
That's why I'd also agree that since the most active or engaged people in a church are the most likely to listen to Christian radio outside of church, and they're the ones who care enough to make issues of of things that bother them, it's those folks churchmen have to watch out for.