GHI Character Display: Bad contrast

I have bought 2 GHI 16x2 character Displays modules (the whole Display, not controller only) but I can barely read anything.
I have to look at it at an angle of about 45° from below to read anything.
I have tried this with both Displays.
My G120 HDR is supplied by the USB DP module with an 6V power supply.
I also tried to dim the backlight by reducing the voltage on the backlight pin, but this does not help eather.
As Test program I used an empty gadeteer Project with Cobra II and chracter Display module connected to Socket R (from RGB)

Any ideas how to improove the contrast of this Display?
If it is like this I can not use it.

both show same contrast? How are you powering the board?

6v is possibly part of your problem. Because the DP is regulating the power, you will get a decrease in voltage. The specs page say 7v - " The power supply is fully functional from 7V to 30V"

Thanks Brett. Yes you are right. 6V is not okay for the DP module.

Ok, my fault.
More power did the trick.
Thank you.