## TL;DR

For signed assets in mux-player, sign playback, thumbnail, storyboard, and drm tokens in one call and pass them as player props.

## Steps

1. For Mux AI audio workflows, attach dubbed tracks with a short-lived presigned source URL and name the track clearly. For signed assets in mux-player, sign playback, thumbnail, storyboard, and drm tokens in one call and pass them as player props.

## When to use

You are seeing this: For Mux AI audio workflows, attach dubbed tracks with a short-lived presigned source URL and name the track clearly. Use this skill when you run into "Mux AI examples: dubbed tracks via presigned URL, multi-token signing for player".

## When not to use

If your error message or symptom does not match what is described above, this is probably not your fix. Search for your exact error text instead of forcing this one to fit.

## Versions

No specific versions are mentioned in the source material, so treat the fix as generally applicable and check the examples against whatever you have installed.

## Why this happens

The original report does not dig into a root cause. It documents the symptom and the fix that resolved it.