I have a tuner app and using Audio Record object for listening mic. I want to understand it works fine for most devices and android versions (even Android 6) but I got error report from customers on Samsung S7 Phones. I looked at similar posts here to avoid this error and it helped me a lot. But now i cannot understand why only S7 phones gives this error while it s working fine on other Android 6 devices.
P.S. I dont have S7 phone so I couldn't have a chance to try something. I just wonder if anyone having similar issues and what could be the problem with S7 phones. Any ideas?
 @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        initAudioRecord(44100, 2048);
        .....
    }
    public void initAudioRecord(int sampleRateInHz, int bufferSizeInBytes) {
            AudioRecord audioRecord = AudioRecordInstance(sampleRateInHz, bufferSizeInBytes);
            if (audioRecord.getState() != AudioRecord.STATE_UNINITIALIZED) {
                if (audioRecord.getRecordingState() != AudioRecord.RECORDSTATE_STOPPED) {
                    audioRecord.stop();
                }
                audioRecord.release();
                audioRecord = AudioRecordInstance(sampleRateInHz, bufferSizeInBytes); 
            }
            audioRecord.startRecording();     
    }
    public AudioRecord AudioRecordInstance(int sampleRateInHz, int bufferSizeInBytes){
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M){
            return new AudioRecord.Builder()
                    .setAudioSource(MediaRecorder.AudioSource.MIC)
                    .setAudioFormat(new AudioFormat.Builder()
                            .setEncoding(AudioFormat.ENCODING_PCM_16BIT)
                            .setSampleRate(sampleRateInHz)
                            .setChannelMask(AudioFormat.CHANNEL_IN_MONO)
                            .build())
                    .setBufferSizeInBytes(2*bufferSizeInBytes)
                    .build();
        }else{
            return new AudioRecord(
                    MediaRecorder.AudioSource.MIC,
                    sampleRateInHz,
                    AudioFormat.CHANNEL_IN_MONO,
                    AudioFormat.ENCODING_PCM_16BIT,
                    bufferSizeInBytes * 2);
        }
    }
}
LogCat:
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.tuner/com.tuner.TunerActivity}: java.lang.IllegalStateException: startRecording() called on an uninitialized AudioRecord.
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3253)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3349)
    at android.app.ActivityThread.access$1100(ActivityThread.java:221)
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1794)
    at android.os.Handler.dispatchMessage(Handler.java:102)
    at android.os.Looper.loop(Looper.java:158)
    at android.app.ActivityThread.main(ActivityThread.java:7224)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1230)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1120)