EmbossMaskFilter strange effect on other drawings

Question

I've tried to use EmbossMaskFilter to create custom Drawable. However I've come across strange behaviour, that when I try to use Emboss it's causing black stripes on edges of other 2d-graphics objects that overlaps with "embossed" drawble bounds.

Am I missing something? maybe some ~pixel blend setting or what?

Example: black stripes on ScrollView "fadings". When I remove Emboss mask they are gone. Also when I've made ImageButton with background drawable using Emboss and front drawable as canvas drawing, this front drawable gets stripes too.

Activity (+main.xml = LinearLayout in ScrollView = http://pastebin.com/031AV6Wp):

public class TestEmbossActivity extends Activity {
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        Paint paint = new Paint();
        paint.setColor(Color.RED);
        paint.setMaskFilter(new BlurMaskFilter(15, Blur.INNER));
        paint.setMaskFilter(new EmbossMaskFilter(new float[] { 1, 1, 1 }, 0.4f, 5, 3f));

        ViewGroup container = (ViewGroup) findViewById(R.id.container);
        for(int i = 0; i < 20; i++) {
            ImageView view = new ImageView(this);
            view.setScaleType(ScaleType.FIT_XY);
            Drawable drawable = new MyDrawable(paint);
            view.setImageDrawable(drawable);
            LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(100, 100);
            params.bottomMargin = 10;
            container.addView(view, params);
        }
    }

    private static class MyDrawable extends Drawable {
        Paint paint;

        private MyDrawable(Paint paint) {
            this.paint = paint;
        }

        @Override
        public void draw(Canvas canvas) {
            Rect bounds = getBounds();
            canvas.drawRect(bounds, paint);
        }

        @Override
        public int getOpacity() {
            return PixelFormat.TRANSLUCENT;
        }

        @Override
        public void setAlpha(int alpha) {
            // TODO Auto-generated method stub
        }
        @Override
        public void setColorFilter(ColorFilter cf) {
            // TODO Auto-generated method stub
        }
    }

}