Use the music note icon for the music files pref.

<?xml version="1.0" encoding="utf-8"?>

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<vector xmlns:android="http://schemas.android.com/apk/res/android"

        android:width="24dp"

        android:height="24dp"

        android:viewportWidth="24.0"

        android:viewportHeight="24.0">

    <path

        android:fillColor="#FF000000"

        android:pathData="M18,3h-5c-0.55,0 -1,0.45 -1,1v8.3a3.88,3.88 0,0 0,-2.9 -0.04c-1.79,0.67 -3.11,2.35 -3.1,4.26A4.483,4.483 0,0 0,10.5 21c2.5,0 4.5,-2.3 4.5,-4.5V6h3c0.55,0 1,-0.45 1,-1V4c0,-0.55 -0.45,-1 -1,-1z"/>

</vector>

    @Override

    public void setupView(AppViewHolder holder) {

        holder.appIcon.setImageDrawable(mContext.getDrawable(R.drawable.empty_icon));

        holder.appIcon.setImageDrawable(mContext.getDrawable(R.drawable.ic_media_stream_on_24dp));

        holder.appName.setText(mContext.getText(R.string.audio_files_title));

        holder.summary.setText(Formatter.formatFileSize(mContext, mMusicSize));

    }