Issue 1:
89 warnings visible in gh-10378, perhaps due to a change in one of our doc build dependencies.

WARNING: duplicate object description of scipy.io.wavfile, other instance in io, use :noindex: for one of them
WARNING: duplicate object description of scipy.io.arff, other instance in io, use :noindex: for one of them
WARNING: duplicate object description of scipy.io, other instance in io, use :noindex: for one of them
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done

Issue 2:
MDCT (DCT type 4) is really important for audio compression research but is missing from SciPy. I started looking into fftpack but... oh my, that code is currently way beyond my comprehension.

So I am for now simply putting it out there: It would be really great to have DCT type 4 and MDCT in SciPy.