Is the Frequency of Current Noise Voltage Dependent?

[jonlg_uk]

Hello I have been doing a set of experiments in order to try and measure the current noise of a thick film resistor. I basically attach a low noise, power supply, to a thick film resistor and slowly increasing the power supplies voltage to that resistor.

I am noticing a strange phenomena when observing the FFT frequency plots.
As I increase the voltage I can see that the current noise decreases in magnitude, yet increases in frequency. I thought that as I increased the voltage I would see the peak get bigger. Can anyone explain this (in terms of electrons bunching and releasing)? I have attached the frequency plots:

 

[Vitina]

Your plot looks similar to white noise generation in some circuits i have played with. These made lower frequency, falling rocks or rain, audio noise at voltages near a threshold and as voltage (and subsiquent current) were increased, the frequencey would increase but reduce in amplitude. But this was atributed quantum or tunneling effects in a pn junction.
I have always been aware of carbon composite resistors having noise, and thought the metalic thin film resistors avoided this.

 

[Vanadium 50]

The OP hasn't been here in seven years, just in case you were expecting a response.

 

[Vitina]

My reminising. It also reminded me of the time I used an aluminized space blanket to create electrotatic sub sonic sound and had this noise showing up on our other equipment. Hate seeing a question just hang there. Thanks