Disabling all cameras make android-screen go crazy!

I need to disable all my cameras to save battery.
before i disable them i draw a back texture to the screen.

It works as expected on my samsung devices but when i do it on my HTC Desire HD the screen goes full retard, showing crazy variations of yellow all over the screen.

Any ideas?

 

if you dont have a camera in the scene, the game is not rendering anything, so the GPU will fill it with junk from its pool of memory, you need to have at least one camera active

 

Thx for the answer!
I acually managed to solve it by first disabling my real camera. Then i added another camera that renders nothing but black background for a second before disabling this camera aswell.

I guess this fills the GPU memory with only black - since the screen now only show black w/o any cameras