KokoroTtsManager.initialize() hangs after ANE fp16 + source_noise commits

[villeneuve-michael]

Description

After the recent commits on main, KokoroTtsManager.initialize() hangs indefinitely and never returns. This is a regression — initialization worked correctly on commit 3826150 (Mar 20) and earlier.

Suspected Breaking Commits

• 2ae0846 — "Add Kokoro TTS ANE optimization (fp16 conversion)" (Add Kokoro TTS ANE optimization (fp16 conversion) #411)
• 4b03d1f — "Fix missing source_noise input in Kokoro TTS models" (Fix missing source_noise input in Kokoro TTS models #412)

Environment

• Platform: iOS (iPad), Swift
• Integration: FluidAudio via Swift Package Manager
• Last working commit: 3826150 (Mar 20, 2026)
• First broken commit: 2ae0846 (Mar 21, 2026)

Reproduction

import FluidAudio

let lexicon = try? TtsCustomLexicon.parse("aegis=ˈiːʤɪs")
let manager = KokoroTtsManager(defaultVoice: "af_heart", customLexicon: lexicon)

// This call hangs indefinitely — never returns or throws
try await manager.initialize()

Observed Behavior

• manager.initialize() never resolves (no return, no error)
• The model cache directory exists and contains files totaling >300 MB
• isModelDownloaded check passes (cache appears complete)

Expected Behavior

manager.initialize() should complete within a few seconds when the model is already cached, as it did on commit 3826150.

Workaround

Pinning the SPM dependency to commit 3826150 resolves the issue:

// Package.swift or Xcode SPM settings
.package(url: "https://github.com/FluidInference/FluidAudio.git", revision: "3826150")

[Alex-Wengg]

@villeneuve-michael it turns out our v2 models on HF weren't suited for ios, v1 default models still worked . hopefully this resolves your issue now

https://huggingface.co/FluidInference/kokoro-82m-coreml/tree/main

[villeneuve-michael]

Thanks for the quick feedback