To be fair to sound engineers, both experienced and fresh, if Barry on keys is playing as if there is no one else in the band, has reduced motor skills so is smacking all sorts of extra notes, is riding that sustain pedal, is giving it his finest Con Belto with octegenarian vibrato while speeding up and is partially deaf so cannot hear anyone else there is not much you can do. I am fully aware that was a long sentence.
Obv I changed Jim's name to Barry to hide his identity.
But the point stands. Any band, no matter what the venue, can suck badly if there is no musical discipline or any mic technique. The nature of volunteers is that this could happen on a Sunday morning or evening. And the congregation/audience will presume it is the sound bod cos the band must be OK. Sound bods do not have it easy.