[cm12.1_golden.nova.20151204] Battery Saver On sets Brighter Screen

[powerumble]

When enabling battery saver the screen gets brighter. It's not possible to set the screen darker, only when the battery saver is disabled. Actually this should be the other way around.

Is there any workaround for this? Maybe some configuration is messed up? Any ideas?

Factory reset/wipe cache didn't solve the problem.
Executing "settings put global low_power 1" in terminal gives the same result.

cm12.1_golden.nova.20151023, cm12.1_golden.nova.20151204 both affected in my device.