[BUG] Claude Desktop completion chime cannot be disabled, plays repeatedly, no app setting exists

### Preflight Checklist

- [x] I have searched [existing issues](https://github.com/anthropics/claude-code/issues?q=is%3Aissue%20state%3Aopen%20label%3Abug) and this hasn't been reported yet
- [x] This is a single bug report (please file separate reports for different bugs)
- [x] I am using the latest version of Claude Code

### What's Wrong?

What's wrong

The Claude Desktop app plays a chime sound on every response completion, with no in-app setting to disable it. On at least one variant, the chime pulses repeatedly for a single response rather than firing once.

Environment

macOS, Claude Desktop app

Prior reports

#36063: same completion-chime bug, closed as not planned
#91237: broader ask covering completion + dictation sounds and the repeat behavior, also closed as not about Claude Code
#52467 references prior precedent for filing Claude Desktop app bugs in this repo per Anthropic support (Fin) guidance, so this does appear to be an accepted venue for Desktop bugs when they involve Claude Code sessions running inside the Desktop app

Reopening as a fresh, narrowly-scoped report since the prior two are locked and inaccessible to non-collaborators.

### What Should Happen?

Actual behavior

A chime plays on completion
Sound is played by the app itself, not the OS: confirmed by disabling macOS Notification Center sound settings for the app and the sound still plays
All in-app notification toggles (response completions, scheduled tasks, code notifications) were disabled and the sound still played
On one environment, the chime repeated multiple times per response instead of firing once

### Error Messages/Logs

```shell

```

### Steps to Reproduce

Steps to reproduce

Open Claude Desktop
Send a message in a chat session
Wait for the response to complete

Expected behavior

A setting exists to disable app-level sound effects (master switch at minimum, separate toggles for completion/dictation sounds preferred)
Regardless of the toggle, the chime should fire once per event, not loop

### Claude Model

None

### Is this a regression?

Yes, this worked in a previous version

### Last Working Version

_No response_

### Claude Code Version

Claude 2.110.0 (dfb2ba) 2026-09-15T05:50:55.000Z

### Platform

Anthropic API

### Operating System

macOS

### Terminal/Shell

Terminal.app (macOS)

### Additional Information

Steps to reproduce

Open Claude Desktop
Send a message in a chat session
Wait for the response to complete

Expected behavior

A setting exists to disable app-level sound effects (master switch at minimum, separate toggles for completion/dictation sounds preferred)
Regardless of the toggle, the chime should fire once per event, not loop

No repository file, test, or entry point is identified; start by determining whether Claude Desktop sound behavior is implemented in this repository or handled by the desktop app. Done means providing an app-level way to disable the completion chime and ensuring one completion produces at most one chime, including the repeated-playback case.

Written by the indexing model from the issue text.