Ensuring Your Audiobook Passes Audible’s QA: 5 Common Mistakes to Avoid
Publishing an audiobook is an exciting step for any author — but failing Audible’s quality assurance (QA) checks can stall your launch and waste valuable time. Audible, through ACX (Audiobook Creation Exchange), has strict technical and content standards. Yet many first-time publishers and self-narrators are caught off guard by common issues.
To help you avoid these pitfalls, we’ve outlined five of the most frequent reasons audiobooks are rejected by Audible’s QA team — and how to avoid them.
Mistake 1: Inconsistent Audio Levels
One of the top reasons for ACX rejections is uneven volume or dynamics between chapters. This creates a jarring experience for listeners and falls short of platform requirements. ACX expects:
RMS levels between -18dB and -23dB
Peak levels no higher than -3dB
If your audiobook hasn’t been properly mastered, these levels may vary significantly. At Kore Sounds, our audiobook mastering process ensures level consistency across every chapter, creating a smooth, professional listening experience.
Mistake 2: Noise Floor Too High
The noise floor is the amount of background sound in your recording — including hiss, hum, or fan noise. ACX requires a noise floor below -60dB, and many home recordings struggle to meet this standard.
Recording in a professional, acoustically treated space is key. Our Nottingham-based studio is built to reduce unwanted sound, using industry-standard microphones (Neumann, DPA) and high-end preamps to capture clean, clear narration. We also apply noise reduction carefully during post-production to ensure compliance without sacrificing audio quality.
Mistake 3: Missing Room Tone or Over-Editing
Some authors over-edit their recordings, removing all silences or cutting audio too tightly. This creates abrupt transitions and an unnatural flow. ACX guidelines recommend maintaining natural spacing and including room tone at the beginning and end of each file for consistency.
Smooth editing is essential. Our editors retain natural pacing while cleaning up noise, ensuring your book flows beautifully from start to finish.
Mistake 4: Incorrect File Formatting
Even a perfectly narrated audiobook can be rejected if the files are incorrectly formatted. ACX requires:
192kbps constant bit rate MP3 files
Sample rate of 44.1kHz
Each file to start and end with 0.5 to 1 second of room tone
No extraneous noise, music, or additional processing
We deliver files that are 100% ACX-compliant and ready to upload — saving you time and avoiding frustration.
Mistake 5: Poor Narration Quality
While ACX may not reject an audiobook purely based on voice performance, poor narration can affect listener reviews and platform visibility. Common issues include:
Mispronunciations
Unclear delivery
Inconsistent character voices or energy
Whether you’re narrating your own book or working with talent, it’s important to deliver a polished, engaging performance. At Kore Sounds, we offer professional narrators, live monitoring, and guidance to make sure your recording connects with your audience.
Get Your Audiobook Audible-Ready
Avoiding these five common mistakes will dramatically increase your chances of passing ACX’s quality check the first time. If you’re unsure whether your audiobook meets the mark, our team is here to help.
We’ve mastered hundreds of hours of Audible-ready audio, and we know exactly what ACX is looking for. Explore our Audiobook Production services or contact us for support.