DDPBluRay 1280kbps with a DD core will have issues detecting proper format

Below will resolve that

```python
def safe_get_audio_format(a_track: Track) -> str:
    if a_track.other_format and isinstance(a_track.other_format, list):
        return a_track.other_format[0]
    else:
        return a_track.format
```