strange behavior of a qprox

hy,

i'm working with a qt110 chip.

so, when i try to read it just normal with the analog input tutorial, everything is fine. i check out the serial monitor, and i see the right values rollin. 1024 if no touch, 0 when i touch it.

but as i built it into my program, i never get a clear value. and the value, that it reads changes very oftly. here my reading function:

void position(){
int links;
int rechts;
links = analogRead(linkerPin);
rechts = analogRead(rechterPin);
Serial.println(links);
if(links < 500){
if(positionValue < 64){
int neuePos = positionValue << 1;
positionValue = neuePos;
}
}

if(rechts < 500){
if(positionValue > 1){
int neuePos = positionValue >> 1;
positionValue = neuePos;
}
}
}

how can it be? is there something in general i have forgotten? any suggestions?

thanks for any reply
nicolas