Troubleshooting

Troubleshooting

Start with the Preflight report. It runs before model loading and usually gives the failing scene, setting, and corrective action.

Symptom	Check first
Workflow opens with red model widgets	Example model files are not bundled. Select installed H3 model, encoders, VAEs, and LoRA equivalents.
Preflight says source is too short	Use a longer source, shorten the Plan, or run only through the last complete scene reported.
AV transition rejects 22 or 56 context frames	AV-mask modes require a shared video/audio boundary. Start with 39 frames.
Scene repeats too much at the join	Confirm Loop Trim is connected and receives Current Shot's trim_frames.
Final audio is missing or wrong	Check all three Audio Policy axes and ensure decoded audio reaches Segment + Checkpoint.
Source audio or motion starts at the wrong place	Use Source Timeline and verify source FPS, skip origin, and the Current Shot window.
A tracked mask is stretched or rejected	Exact mode needs one static mask or the exact raw scene-frame span. Use Loop Mask Slice.
Masked editing changes the wrong area	Use the same white = generate/preserve convention in Grid Preview and Apply Target Mask.
Resume refuses a checkpoint	Read the structured mismatch: it identifies the changed scene, field, saved value, and current value.
Review video has no sound	Confirm decoded audio is connected. If FFmpeg is unavailable, inspect the PyAV fallback warning.
Plan or editor looks stale after an update	Reload the browser. Versioned frontend modules usually avoid a full browser-data clear.
H3-Multishot or SolAttn conflicts	Keep known wrappers installed and read the exact compatibility error before changing patch priority.
Another H3 Motion Context pack is installed	Both supported packs use distinct public node IDs. Use Patch Priority only for a recognized legacy load-order conflict.

Useful diagnostics

• Chain Preflight — timing, source coverage, references, compatibility, and resume eligibility without loading H3.
• Seam Probe — correlation, timing offset, level step, and ambience-floor change across an audio boundary.
• Run Manager — saved Plan, prompt history, assets, and output folder.
• Load Manifest — recover and assemble accepted work without rerendering.

For runtime patch details, saved 0.4 graphs, and supported coexistence paths, use Compatibility and migration.

If the problem remains reproducible, open a GitHub issue with the Preflight report, ComfyUI version/commit, workflow JSON, pack commit, and the shortest relevant log excerpt.