I have recently noticed a degradation in the audio quality generated with Gemini 2.5 Pro TTS in Google AI Studio.
The generated speech now occasionally contains very short interruptions, micro-cuts, or discontinuities in the audio. They sound like tiny sections of the waveform are missing or being abruptly interrupted.
This behavior was not noticeable, or was significantly less frequent, in previous generations using the same model and similar prompts.
Model
Gemini 2.5 Pro TTS
Google AI Studio
Problem
During TTS generation, the resulting audio sometimes contains:
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Very short audio cuts or interruptions.
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Small discontinuities between phonemes or words.
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Occasional unnatural transitions in otherwise continuous speech.
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A noticeable reduction in perceived audio consistency compared with previous generations.
The problem does not necessarily occur at the same position every time, which makes it seem related to the generation process rather than to the input text itself.
Steps to reproduce
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Open Google AI Studio.
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Select Gemini 2.5 Pro TTS.
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Generate speech from a normal paragraph or narration.
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Listen carefully to the generated audio.
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Repeat the generation several times using the same text.
In some generations, small cuts/glitches can be heard even though the text and settings have not changed.
Expected behavior
The generated speech should be continuous and smooth, without missing audio samples, sudden micro-pauses, clicks, or interruptions between phonemes.
Actual behavior
Some generations contain short but clearly audible discontinuities or micro-cuts that reduce the quality of the generated speech.
This is particularly noticeable when using the audio for narration, where even very small interruptions can be distracting.
Frequency
Intermittent, but frequent enough to be noticeable across multiple generations.
When I started noticing it
Approximately around September 2026.
The issue appears to be more noticeable recently compared with earlier generations made with Gemini 2.5 Pro TTS.
Additional information
It would be useful to confirm whether there have been any recent changes to:
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The Gemini 2.5 Pro TTS inference pipeline.
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Audio post-processing.
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Audio encoding or WAV generation.
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Streaming/chunk reconstruction.
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Sampling or generation parameters used internally by Google AI Studio.
Thank you.