Hi,
I managed to compile torchaudio with sox in Windows 10, but is a bit tricky.
Unfortunately the sox_effects are not usable, this error shows up:
RuntimeError: Error opening output memstream/temporary file
But you can use the other torchaudio functionalities.
The steps I followed for Windows 10 64bit are:
#############################
TORCHAUDIO WINDOWS10 64bit
#############################
Note: I mix some command lines unix-like syntax, you can use file explorer or whatever
preliminar arrangements


Download sox sources
$ git clone git://git.code.sf.net/p/sox/code sox


Download other sox source to get lpc10


$ git clone https://github.com/chirlu/sox/tree/master/lpc10 sox2
$ cp -R sox2/lpc10 sox


IMPORTANT get VisualStudio2019 and BuildTools installed

lpc10 lib
4.0. Create a VisualStudio CMake project for lpc10 and build it
Start window -> open local folder -> sox/lpc10
(it reads CMakeLists.txt automatically)
Build->build All
4.2. Copy lpc10.lib to sox
$ mkdir -p sox/src/out/build/x64-Debug
$ cp sox/lpc10/out/build/x64-Debug/lpc10.lib sox/src/out/build/x64-Debug

gsm lib
5.0. Create a CMake project for libgsm and compile it as before with lpc10
5.1. Copy gsm.lib to sox
$ mkdir -p sox/src/out/build/x64-Debug
$ cp sox/libgsm/out/build/x64-Debug/gsm.lib sox/src/out/build/x64-Debug

sox lib
6.0. Create a CMake project for sox in VS
6.1. Edit some files:
CMakeLists.txt: (add at the very beginning)
 project(sox)
sox_i.h: (add under stdlib.h include line)
#include <wchar.h> /* For off_t not found in stdio.h */
#define UINT16_MAX  ((int16_t)-1)
#define INT32_MAX  ((int32_t)-1)

sox.c: (add under time.h include line)
`#include <sys/timeb.h>`

6.2. Build sox with VisualStudio
6.3. Copy the libraries where python will find them, I use a conda environment:
$ cp sox/src/out/build/x64-Debug/libsox.lib envs\<envname>\libs\sox.lib
$ cp sox/src/out/build/x64-Debug/gsm.lib envs\<envname>\libs
$ cp sox/src/out/build/x64-Debug/lpc10.lib envs\<envname>\libs

torchaudio
$ activate <envname>
7.0. Download torchaudio from github
$ git clone https://github.com/pytorch/audio thaudio
7.1. Update setup.py, after the “else:” statement of “if IS_WHEEL…”
$ vi thaudio/setup.py
#if IS_WHEEL…
else:
    audio_path = os.path.dirname(os.path.abspath(__file__))

    # Add include path for sox.h, I tried both with the same outcome
    include_dirs += [os.path.join(audio_path, '../sox/src')]
    #include_dirs += [os.path.join(audio_path, 'torchaudio/sox')]

    # Add more libraries

    #libraries += ['sox']
    libraries += ['sox','gsm','lpc10']

7.2. Edit sox.cpp from torchaudio because dynamic arrays are not allowed:
$ vi thaudio/torchaudio/torch_sox.cpp

 //char* sox_args[max_num_eopts];
 char* sox_args[20]; //Value of MAX_EFFECT_OPTS

7.3. Build and install
$ cd thaudio
$ python setup.py install

It will print out tons of warnings about type conversion and some library conflict with MSVCRTD but “works”.
And thats all.