java.lang.NoClassDefFoundError for AudioSource in Util.java

[umutgur]

In cafe.adriel.androidaudiorecorder.Util.java file, AudioSource could not found

public static omrecorder.AudioSource getMic(AudioSource source,
                                                AudioChannel channel,
                                                AudioSampleRate sampleRate) {
        return new omrecorder.AudioSource.Smart(
                source.getSource(),
                AudioFormat.ENCODING_PCM_16BIT,
                channel.getChannel(),
                sampleRate.getSampleRate());
    }

Here is the screenshot from error,

Thanks