[Bug][macOS] Advanced Voice terminates after AudioConverter invalid-property error

What version of the Codex App are you using?

• ChatGPT/Codex Desktop: 26.820.60940
• Bundled Codex runtime: 0.150.0-alpha.8

What platform is your computer?

• macOS 26.1 (25B78)
• Apple Silicon

What issue are you seeing?

During an active Advanced Voice session, a red error toast briefly dropped down from the top of the app and disappeared before it could be read. Advanced Voice then stopped working and had to be restarted.

The user did not change the microphone, speaker, audio route, or any Voice setting.

The macOS unified log records this at the matching time:

2026-08-27 06:31:14.007
Codex (Service) (AudioToolboxCore)
AudioConverter: The <private> SetProperty call returned 1886547824
for property 1886547309 with size 4.

The returned OSStatus is 0x70726F70 / 'prop', indicating an invalid or unsupported audio-property operation.

Additional timing evidence:

• At 06:30:53.861, ChatGPT created a standalone audio device clock for the built-in speaker.
• The app also initialized and retired a ScreenCaptureKit stream at 06:30:53.
• The AudioConverter property failure followed about 20 seconds later.
• No full ChatGPT process crash or macOS crash report was recorded.

This timing is correlation, not proof that screen capture caused the audio failure.

Steps to reproduce

The exact trigger is not yet deterministic:

1. Start Advanced Voice in Codex Desktop on macOS.
2. Continue an active Voice conversation.
3. During the session, allow Codex to inspect current screen context.
4. Observe whether a brief red error toast appears.
5. Observe whether Advanced Voice terminates immediately afterward.

Expected behavior

Advanced Voice should remain active. An internal audio-property failure should be handled or recovered without killing the Voice session.

If recovery is impossible, the error toast should remain visible long enough to read, be retained in the task timeline, and include a copyable diagnostic reference.

Actual behavior

A brief red error toast appeared and vanished. Advanced Voice stopped. The visible toast text was not preserved, leaving only the macOS AudioToolbox log as evidence.

Related reports

This is related to, but not an exact duplicate of:

• #37098 — Voice disconnects after the app is backgrounded.
• #35474 — Voice disconnects after a WebSocket reset.

This report concerns a local AudioConverter invalid-property failure during an active session.