pptx to mp3 conversion is not really a standard file conversion, mainly because of the different nature of both these two file types.
Since PPTX files are PowerPoint presentations and it is possible to add multimedia content (both audio and video) to the slide, one way to look at pptx to mp3 export is the potential recovery of any used .mp3 from the presentation. In this case, using PowerPoint or a similar tool will work for you.
Another completely different approach is the transcription of text from a PowerPoint presentation and saving the computerized speech as MP3 audio. For this you have to use dedicated text-to-voice software solutions, for example, Balabolka.
Updated: January 22, 2024