Conversion of m4a files to pdf file format

As far as we know, it is not possible to "convert" MP4 multimedia files as PDF documents. Nonetheless, some software might allow users to embed an MP4 file to a PDF document which can then be played when the PDF is viewed. Though Flash is the preferred content for PDFs nowadays and not just any multimedia files. Also transcription service / software can be used to produce a text from voice and eventually save it as PDF. 

Open M4A file    Open PDF file

Related software

DriveConverter for Google Drive

Google Chrome extension for Google Drive