Crash or missing codec error when exporting audio in AMR format

[dozzzzer]

Bug description

The lack of a suitable codec for the AMR format causes Audacity to crash or prevent audio from being exported.

Steps to reproduce

1. Grab some audio, mono or stereo
2. File > Export Audio
3. Select the format: AMR or set it to "Custom FFmpeg Export" and then click the "Open custom FFmpeg format options" button and select AMR in the formats column
4. Select an arbitrary sample rate and bitrate (if applicable)
5. Click Export
6. Observe

Expected behavior

Audio exported in AMR format.

Actual behavior

In some cases, it causes a crash. In others, it throws the missing codec error message:

Audacity Version

Audacity 3.7.x

Operating system

Windows, macOS, Linux

Additional context

No response

[kryksyh]

@dozzzzer I can't reproduce the issue on macOS with ffmpeg 7.1 installed from homebrew, the audio can be exported and then imported back without errors or crashes.

[kryksyh]

I can't reproduce the issue on windows 10 with ffmpeg 7.1 installed from https://github.com/BtbN/FFmpeg-Builds/releases.