I did a google search and here are a couple of free wma to aiff and wav to aiff file converters.
It looks like it is a batch conversion.

Don't ask as I don't have any experience with either.

https://convertio.co/wav-aiff/

https://www.freeconvert.com/wma-to-aiff


I get most of my exercise these days from shaking my head in disbelief.


64 bit Win 10 Pro, the latest BiaB/RB, Roland Octa-Capture audio interface, a ton of software/hardware