np_to_mp3 test failure

[stephengrice]

=========================================================================================== FAILURES ===========================================================================================
_______________________________________________________________________________________ test_convert_mp3 _______________________________________________________________________________________

    def test_convert_mp3():
        if os.path.exists("song.mp3"): os.remove("song.mp3")
    
        sample_rate = 44100
        signal = sin(65.406, 5, 2, sample_rate)
>       np_to_mp3(signal, sample_rate, "song.mp3")

test/test_lib.py:11: 
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 
plaintext_daw/lib.py:54: in np_to_mp3
    soundfile.write(mp3_path, audio_raw_int16, sample_rate)
../../.local/lib/python3.8/site-packages/soundfile.py:340: in write
    with SoundFile(file, 'w', samplerate, channels,
../../.local/lib/python3.8/site-packages/soundfile.py:653: in __init__
    self._info = _create_info_struct(file, mode, samplerate, channels,
../../.local/lib/python3.8/site-packages/soundfile.py:1476: in _create_info_struct
    info.format = _format_int(format, subtype, endian)
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 

format = 'mp3', subtype = 'MPEG_LAYER_III', endian = 'FILE'

    def _format_int(format, subtype, endian):
        """Return numeric ID for given format|subtype|endian combo."""
        result = _check_format(format)
        if subtype is None:
            subtype = default_subtype(format)
            if subtype is None:
                raise TypeError(
                    "No default subtype for major format {0!r}".format(format))
        elif not isinstance(subtype, (_unicode, str)):
            raise TypeError("Invalid subtype: {0!r}".format(subtype))
        try:
            result |= _subtypes[subtype.upper()]
        except KeyError:
            raise ValueError("Unknown subtype: {0!r}".format(subtype))
        if endian is None:
            endian = 'FILE'
        elif not isinstance(endian, (_unicode, str)):
            raise TypeError("Invalid endian-ness: {0!r}".format(endian))
        try:
            result |= _endians[endian.upper()]
        except KeyError:
            raise ValueError("Unknown endian-ness: {0!r}".format(endian))
    
        info = _ffi.new("SF_INFO*")
        info.format = result
        info.channels = 1
        if _snd.sf_format_check(info) == _snd.SF_FALSE:
>           raise ValueError(
                "Invalid combination of format, subtype and endian")
E           ValueError: Invalid combination of format, subtype and endian

../../.local/lib/python3.8/site-packages/soundfile.py:1434: ValueError
=================================================================================== short test summary info ====================================================================================
FAILED test/test_lib.py::test_convert_mp3 - ValueError: Invalid combination of format, subtype and endian
================================================================================ 1 failed, 24 passed in 23.46s

Not sure what the fix is here. I may have something set up incorrectly. @LTstrange can you help me with this? Have you seen this before?

I should have ran the tests before merging your PR, but I forgot to. So I have to open an issue instead 😁

[LTstrange]

I resolved the previous error, but more errors have emerged.

[LTstrange]

This problem has been solved by using pydub and ffmpeg, rather than using soundfile library.
Fixed in branch #10.