Changing ISO setting in Google Glass

Question

I am trying to change the ISO setting in the camera of the Google Glass by using the camera API according to

Camera.Parameters parameters = cameraObject.getParameters();
String isoStr = parameters.get("iso"); 
int target = 800;
parameters.set("iso", target);
cameraObject.setParameters(parameters); 

However, this changes nothing in my app. Is this not supported for the Google Glass? Is there some workaround?

Note:

• I have checked that my starting ISO value is 100

• The allowed values are:

  iso-mode-values=auto,100,200,400,800
  

• I have tried this on two android phones and it's working.