Three engineers had worked the venue. Each had spent at least two hours tuning, EQ-ing, and adjusting. Each had pronounced the system 'good.' The client disagreed. 'There's something wrong,' she said. 'It sounds muddy.' The engineers exchanged the knowing glances of professionals dealing with a difficult client.

The client ran a SonaVyx diagnostic. The AI analysis returned in eleven seconds with a health score of 64/100 and a primary finding highlighted in red: 'Ground loop hum detected at 100 Hz and harmonics (200, 300, 400 Hz). Estimated level: -38 dBFS. Harmonic pattern consistent with electromagnetic coupling rather than ground potential difference.'

Three engineers had missed it because 100 Hz hum sits right in the range where room modes, proximity effect, and speaker response variations all compete for attention. It blended in. The ear adapted to it. But the measurement didn't adapt — the FFT showed clear, narrow peaks at 100 Hz and integer multiples, with a harmonic decay pattern that distinguished magnetic coupling from a ground loop.

The source was a lighting dimmer rack sharing a power circuit with the audio system. A power conditioner on the audio feed eliminated the hum. The health score jumped to 89/100. The three engineers listened to the corrected system. 'Actually,' said one, 'I always thought the low-mids were a bit thick.'

The Moral: AI doesn't have ego, fatigue, or hearing adaptation. SonaVyx's AI diagnostic examines every frequency bin objectively, finding problems that experienced ears normalize. Three engineers and two hours each, or one AI analysis in eleven seconds — sometimes objectivity wins.