SONY VAIO Pro 13 HDMI to VGA Screen is randomly twinkling

Recently, I bought a SONY VAIO Pro 13 Win8 NB.
It's nice in Win8 experience, elegant in the shape with very low weight.
However, I've tried it's HDMI output to screen with 1920x1080 resolution, the result is:

• HDMI out to screen HDMI port with HDMI line: it's work normally.
• HDMI out to screen VGA port with build-in HDMI-VGA adapter: the screen is randomly twinkling.

The result repeats while changing different screens or adapter lines. Also, I attempt to find updates and newest drivers from Windows and SONY, all updates were installed and patched, the problem still exists. Finally, I bought a new HDMI-VGA adapter (about 28 USD, support 1920x1080 resolution), the twinkling problem never happens. Obviously, SONY reduces it's cost in the HDMI-VGA adapter, even it may be worth about 10 USD cost only. But, I feel very uncomfortable on the brand (also complain it's Made in China quality) since all my smartphones and pads are SONY products.

Adapter on the top is about 28 USD, the bad-quality adapter on the bottom is included in SONY VAIO.