problem with reading a file path with audioread

Hello,

I haven't used MatLab in a long time but I came back to it just to read some wav files and save the samples in a txt file. The only thing I did was to create a string with the absolute path and then use audioread(filename); but I get an error. I find this weird since it's very simple code and I've done it before.

>> filename='C:\Users\Diana\Documents\IFC\imagenesTAREA2\aH.wav';
>> [y,Fs]=audioread(filename);
Error using audioread (line 74)
The filename specified was not found in the MATLAB path.

I have tried copying the file to the MATLAB folder and using a relative path but I still get the same error. Does anyone know what could be the problem?

btw I'm using ML2016

Thanks!