8/31/20 – The current problem with WAV sounds not playing back in PDFs has recently been a topic of discussion on the Adobe Acrobat Community Support forum. Until the Acrobat Reader sound playback problem is resolved, TheABCD.com recommends using the free Foxit Reader which can be downloaded here:  https://www.foxitsoftware.com/pdf-reader/  Foxit Reader has been tested, works on the latest Windows 10 OS and is also available for Apple computers.  Foxit Reader requires no registration. During installation of Foxit Reader, choose “Custom Installation” and check mark to disable the “ConnectedPDF” option.  Please note: Acrobat Mobile Reader has never worked for WAV sound playback on Android mobile devices. For WAV sound playback on Android devices, we recommend EZ-PDF Reader. WAV files are critical for audio study because internet audio formats are non-standardized and have audible artifacts – making them unsuitable for a reliable audio engineering and production education. Please email me using the contact form if you have any questions. Stay well, all the best, Steve Carr