Removing the noise of the README example breaks the results

[NikVard]

Hi Etienne, in the README example I tested the Modulation Index method (among others) and all is good, until I remove the noise. Setting the noise to 0 and by having a completely clean and highly-coupled signal breaks the plot results. Is this an expected artifact of calculating values from signals that are simply not there (filtering outside the 10Hz/100Hz does not yield anything), or is there something else that I am overlooking?

Thanks in advance, great job with the toolbox!