10 Techniques To Spot AI-Generated Audio

10 Techniques To Spot AI-Generated Audio Banner
Gareth Shelwell author profile photo
Gareth Shelwell Published: July 29, 2025
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Are you looking for straightforward, actionable advice on how to spot AI-generated audio?

In this blog post, we'll walk through 10 techniques you can use to identify whether Artificial Intelligence was used to generate the audio. We’ve also included AI-generated audio samples, showing you exactly what to look for. The goal of this blog is to arm you with practical techniques to help you tell real speech from synthetic sound.

1. Unnatural Prosody

Humans bring life to our words when we speak. It happens naturally through shifts in pitch, stress, rhythm, and tempo. It’s instinctive! We raise our pitch at the end of a question and drop it for a statement. Key words like “urgent” or “now” are stressed to drive the message home.

Now think about those automated scam calls or AI-generated voices you’ve probably heard. They sound off. Like the life’s been drained out. Questions fall flat instead of lifting, and key words get buried in the sentence. That lack of emotion or natural emphasis can strip the message of clarity, urgency, and most importantly, believability. The pacing feels steady. Too steady. As if it came from an algorithm, not a human mouth. If it sounds flat like a robot reading a script, that’s probably what it is.

EXAMPLE 1

No Emphasis Where It Matters

In this example, the AI voice carries emotion, but it's the wrong kind. It misses the natural urgency you'd expect when someone says, 'This is urgent! Act now!'

2. Missing Micro-Pauses & Fillers

Real speech is full of tiny pauses, stumbles, and hesitations. These little bring authenticity to the way we speak. We pause to think, breathe naturally between thoughts, and sometimes even change direction mid-sentence. These quirks are what make speech feel real.

Ever noticed how synthetic voices often skip all that? AI delivers lines with unnatural smoothness. Breezing through sentences without missing a beat. There’s no pause to collect a thought. No “uh.” No “um.” Nothing that sounds remotely human. You might even catch an odd delay right before a reply. That’s not someone thinking. It’s the system stalling while it generates a response. The gap feels calculated, breaking the natural back-and-forth flow that conversations usually have. Real people don’t talk like that, and your ears know it.

EXAMPLE 2

Missing The Human Touch

In this clip, the AI keeps a steady pace. While micro-pauses and filler words may sound odd in isolation, they add realism when part of a natural sentence.

3. Stilted Sound Blends

As humans, our words don’t come out like they’re typed on a keyboard. We blend sounds together without even thinking about it. “Don’t you” becomes “don’tcha.” “Did you” turns into “didja.” “What are you” slides into “whatcha.” This isn’t laziness. It’s how real speech flows when it’s natural. You hear it without even noticing. But when a voice bot says it? You notice. It sounds stiff, like it’s afraid to get it wrong.

Have you ever heard AI pull this off convincingly? Me neither. Synthetic speech tends to separate every word, like it’s reading straight from a pronunciation guide. Every. Single. Word. Gets. Its. Own. Space. “Could you” comes out as two sharp, distinct words instead of the casual, blended “couldja.” That’s your clue you’re not listening to a genuine voice.

EXAMPLE 3

Too Perfect To Be Human

Humans tend to blend sounds together, which adds authenticity to speech. In this clip, the AI enunciates each word with unnatural precision. We rarely speak this clearly in real life.

4. Flat Emotion & Volume

Human voices don’t stick to one pitch or volume. When we receive good news, we find it hard to contain our excitement. “We’re having a boy!” Our tone rises when we’re excited. Softens when we’re sad and sharpens when we’re angry. Even within a single sentence our pitch and intensity changes to match the way we’re feeling. It all ties together in a way that just seems right.

Ever noticed how fabricated voices struggle with this? It’s like their voice is stuck in neutral. The delivery feels emotionless. Other times, the tone swings too far in the other direction. It jumps from flat to theatrical, and the result just feels off.

EXAMPLE 4

Emotion Without Feeling

In this clip, the AI’s delivery lacks genuine emotion. The tone doesn’t match the meaning of the words, making the speech feel flat and disconnected.

5. Recycled Phrases

In real speech, we mix up our words, rephrase on the fly, and change how we say things, even when we repeat ourselves. The rhythm, tone, and inflection shift naturally as we speak, creating speech that feels alive and spontaneous.

This is where AI-generated audio starts to sound unnatural. You might hear the same word or phrase repeated with identical delivery, like “I can help with that, I can help with that…” where a human would stop or switch it up. AI generators often reuse the same waveform snippets for common words. So if you notice the exact same inflection cropping up again and again, pay attention. That kind of repeat pattern is a clear sign the voice was built. Not spoken.

EXAMPLE 5

Same Phrase, Same Delivery

In this clip, the AI repeats “I can help with that” across multiple sentences with identical tone and rhythm. When delivered by a human, we tend to adjust delivery to suit the context or to emphasise a point.

6. Static Background Noise

In real conversations, background noise moves with us. The hum of a room shifts as someone moves, ambient sounds fade in and out, and echoes match the space. Think about a phone call with someone at work, you might hear chatter or a keyboard clacking in the background.

Synthetic audio has trouble getting this right. AI might layer in hiss, static, or fake room tone to sound more real, but it stays frozen. The background doesn’t change with the voice, no rise, fall, or sense of space. Sometimes it even loops, so you’ll hear the same pattern repeat. When the ambient noise doesn’t match the voice’s environment, like when the voice sounds too close while the background echoes like a hall. That mismatch between voice and space is a classic deepfake slip.

EXAMPLE 6

Background Doesn’t Match The Movement

In this clip, the AI says they’re moving, but the background stays the same. In real life, ambient noise would shift with movement. That disconnect between action and sound is the giveaway here.

7. Channel & Mic Jumps

In genuine audio, a person’s voice stays consistent. The microphone’s tone, quality, and position don’t suddenly change without a reason. If the speaker moves or turns their head, you might notice a slight shift in volume or a bit more room echo, but it all fits the environment.

Ever been on a call where the voice suddenly goes from crystal clear to it’s like they’re talking through a pillow? That’s the kind of weird jump you’ll catch in fabricated audio. One second, it’s studio-level crisp, the next it sounds like the speaker fell into a tunnel. The voice might start out close, then suddenly go echoey and distant mid-sentence. The channel balance can jump too, with the voice suddenly leaning left or right in your headphones when it shouldn’t. It’s the kind of error no real speaker would make.

EXAMPLE 7

Sudden Audio Issues

Listen closely when the AI says “optimizing your output.” The audio suddenly muffles for no clear reason. While this can happen in real recordings, it’s a common red flag for AI-generated audio.

8. Jargon & Proper-Noun Flubs

In human speech, names, slang, abbreviations, and brand terms roll off the tongue naturally. Real speakers know how to handle them, stressing the right syllables, pronouncing them the way insiders would, and making it all sound effortless. You expect someone familiar with the subject to nail these without a second thought.

That’s where fake speech starts to show its cracks. You’ll hear odd stress patterns or pronunciations that no native speaker would use. Familiar brands like Bose might come out as bohs or boh-say, breaking the illusion of expertise. AI fumbles jargon and abbreviations too, saying S-O-C instead of sock (how insiders say Security Operations Center) or S-Q-L instead of sequel. These slip-ups make synthetic speech stand out when it should blend in.

EXAMPLE 8

Mispronouncing Brands

In this clip, the AI mispronounces both Moët and IKEA. With newer or less common brands, the AI may not have been trained on the correct pronunciation. These mistakes are a common sign of synthetic speech.

9. Contextual Delivery Errors

When we quote movies, we don’t just repeat the words. We perform them. Think about it. No one casually mutters “I’ll be back” in a monotone voice. You lower your pitch, throw on your best (or worst) Schwarzenegger impression, and deliver it with attitude. Or when someone yells “Say hello to my little friend!” you don’t just say it, you become Scarface for a second, fake accent and all.

It’s instinctive. We add personality, humour, and energy without even thinking about it. It’s how we bring those lines to life, and it’s a perfect example of how natural human speech carries rhythm, emotion, and style that AI still struggles to replicate. It delivers catchphrases in the same flat tone as the rest of the sentence, failing to capture the character or intent behind the line. If a famous quote sounds lifeless or out of place, take it as a red flag!

EXAMPLE 9

All Words, No Performance

In this clip, the AI delivers the line “Say hello to my little friend” without the intensity or timing that make it iconic. The punchline that follows lands awkwardly, missing the impact because of the poor delivery.

10. On-the-Spot Challenge

If you’re suspicious that a voice is synthetic, put it to the test! Ask the speaker to read something fresh on the spot like today’s date, a phone number, or even deliver a famous movie quote in character. AI can struggle with live improvisation. When forced to generate new audio on demand, it often reveals itself through glitches, flat delivery, or awkward prosody, especially when reading serial codes.

AI tends to read numbers in a flat, and evenly paced rhythm, with little to no natural variation. And because numbers don’t carry meaning the way words do, there's nothing for the AI to latch onto, making the delivery sound even more robotic.

EXAMPLE 10

Put It to the Test

This example was created using the latest AI audio tools, yet it still botches the delivery of Buzz Lightyear’s iconic line: “To infinity and beyond!”

Wrapping Up

When it comes to AI-generated videos, you’ve got two senses on the job. Your eyes catch bad lip-sync, odd lighting, or unnatural expressions, and your ears pick up audio glitches.

AI-generated audio leaves you with just one: your ears, which makes fakes harder to spot. Real speech is a bit rough around the edges, and that’s what makes it sound human. If something sounds overly smooth, lifeless, or off, trust your gut. Slow down, put on your skeptic’s hat, and put those 10 techniques to work. The more you listen for the subtle tells, the harder it’s for synthetic speech to slip past you.

Frequently Asked Questions

What Tools Are Available To Help Detect If It's AI-Generated Audio?

These 10 simple listening tricks are a great place to start. You don’t need to be an expert, just trust your ears. But sometimes, you need to go a step further. When your ear alone isn’t enough, there are purpose-built tools designed to help spot synthetic audio. Here are some of the most effective options available:

  • Resemble Detect: A tool from Resemble AI designed to analyze audio clips and determine the likelihood that they are synthetic. It checks for telltale markers like spectral patterns and prosody inconsistencies.
  • Deepfake-o-meter (from Michigan State University): A free research tool where you can upload audio (or video) to scan for signs of AI generation. It compares the clip against common deepfake models.
  • Deepware Scanner: A tool designed to spot synthetic voices and video by analyzing the telltale signs of AI-generated content. It helps flag clips that sound a little too perfect to be real.
  • Sensity AI: A commercial platform that helps detect deepfakes, including synthetic audio, in real time. It’s built for organisations that need fast, reliable protection.
  • Reality Defender: A real-time detection tool that spots deepfake audio, video, and other manipulated media. It runs behind the scenes, using multiple models to flag fakes across platforms and protect critical communication.

Other Strategies:

  • Spectrogram Analysis: Check the spectrogram using tools like Audacity or Adobe Audition. Real voices leave messy, varied patterns, while synthetic ones often show smooth, uniform bands that stand out on the visual map.
  • Metadata Scrutiny: Genuine audio files often contain metadata showing the device used, date, and format. AI-generated or manipulated audio may have missing, sparse, or inconsistent metadata. Tools like ExifTool or MediaInfo can help uncover these details.
  • Contextual Verification: Cross-check the speaker’s known voice, mannerisms, and tone. If something feels off, look for proof, like a post on their official account, their website, or another trusted source. If it’s real, you’ll find a clear trail to back it up.
  • Human-Led Forensic Review: When the stakes are high, trained audio forensic teams can spot artifacts and inconsistencies that even the best tools miss. This isn’t your first line of defence, but it’s a powerful option when you need expert confirmation.

Can AI Voices Mimic People I Know?

Yes. With enough clear audio, AI can generate speech that sounds alarmingly close to someone you know, even a loved one. It might not get every emotional nuance or natural quirk spot on, but it can match the tone, pitch, and rhythm well enough to fool someone who isn’t expecting it. That’s why voice impersonation is becoming a real concern in scams and deepfake fraud.

If a familiar voice sounds strange, too polished, or comes with an odd or urgent request, slow down and fact-check before you act.

Gareth Shelwell author profile photo
Written by Gareth Shelwell

An Operations Manager dedicated to helping you safely swim amongst the internet of phish!

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