https://www.mymeetings.com/netconferencing/WebExOverview.php?tabname=

View a WebEx recorded meeting (wrf file)
Download the WebEx Player to view recordings made during WebEx online meetings and webinars.

Download: Install Meeting Manager

WebEx Meeting Manager 
The WebEx meeting service automatically downloads, installs and configures Meeting Manager, the first time you start or join a meeting. However, some locked-down systems restrict this automated setup, so you may need to download and run the Meeting Manager installer for your particular platform below. The installer is useful only if your system does not allow you to automatically install software directly from a Web site.

Before you set up Meeting Manager, you should test your system to see if it meets the minimum system requirements for running a WebEx meeting. 

Uninstalling Meeting Manager
To uninstall or remove Meeting Manager from your computer, use the Windows Add/Remove Programs utility. Once you run the utility, select WebEx from the list of installed programs and follow the instructions.
 

Once it is installed you will be able to both see the webcast and hear the sound.