Sony 52EX700 white balance/ bluish tinge

Picture mode: Cinema or custom
Backlight 5
Contrast 90
Brightness:50
Colour: 50
Hue: 0
Sharpness: 0
Colour temperature Warm2
Noise reduction Off
Mpeg noise reduction Off
Motionflow Standard
Film-mode Auto 1
Black corrector Off
Adv. Contrast Enhancer On or Off
Gamma 0
Auto Light Limiter Off
Clear White Off
Live Colour Off
R Gain 0
G Gain 0
B Gain 0
R Bias 0
G Bias 0
B Bias 0
Light Sensor Off

Sony 52EX700 LED (edge lit)
This TV is excellent yet also extremely frustrating. I have one more week if I want to return the TV so I need some advice on the settings before I make a decision whether to keep it or not.
The TV is only used in very dark room.
Anyway, as reported by Cnet, home theater magazine and on AVSforums, the picture in the darker scenes has a bluish tinge to it and indeed the default custom settings with all advance feature off produce bluish tinge picture clearly visible in chapter 5 Pandorum blu-ray and other darker movies. My blu-ray is Sony SB360 set to YCBCR 4:4:4, deep color 12 bit, picture mode is standard. I've tried different settings on the player but the bluish tinge remains.
Now, the minute I turn the ambient light sensor ON, set the TV to cimena, blue-ray player to standard settings and the picture is -you could say perfect.
The settings above will look the same; however with the sensor on it is a far better picture and no blusih tinge.

The advice I need is how do I get the picture looking the same way without the sensor on

Or: How do I adjust the white balance settings (without a color meter) to get rid off the bluish tinge.
I've used HD basic and AVS patterns for hours to get the color and tint almost perfect yet the bluish tinge remains.
I can put on a darker movie and lower the B-bias to -5, which gets rid off the bluish tinge, but the picture in shadows now looks different.

Thanks to both of you for your replies.
As far as Cnet goes, no, they were not able to rid the bluish tint out, however saying that they Never test with any of the advance features On.
Yes, I did try several settings including Cnet which by the way were so blue it reminded me of the Caribbean. The home theater magazine was better but still bluish.
So as you can tell I hate the bluish tinge.
Now to Michael, when you say put up a grayscale pattern and adjust the bias controls until the blue on the dark goes away? Do you mean to just lower the B-bias like I did or All three bias must be adjusted, in which cases is there any rule if you lower B-bias by –5 the green and red should go up approximately to??
Thank you

Thank you again
Maybe the set is producing more blue in darker scenes as reported in many places,
and maybe that's the way it is however what I don't understand how every one does not see that.
I will need to make a decision in next few days "to keep or not to keep"
Thanks again

Just and update to both of you. Contacted Sony Tech support who contacted his manager and they both agreed not to send a service guy to look at the TV for in their opinion it can’t be fixed. He asked me to return it to Best Buy for exchange, which I did but I took the 52EX500 LCD instead. No bluish tinge at all. Black. Despite being LCD not LED and cheaper I’m definitely much more satisfied with this TV. I loved the EX700 just couldn’t live with the blue.
Thanks again for you help.