Python, resampling tools dont work as expected
The problem is that if your wav file stores samples as integers (typically 16 bit signed), $\texttt{scipy.io.wavfile.read()}$ returns an array of integers. If this is the case, you want to convert your signal into a floating point representation before applying resampling. For a wav file which stores values as N bit signed integers, this can be done by:

// Convert y to float array, with values in the interval [-1.0,1.0]
y_float = float(y / (2.0**(N-1) + 1))