Chrome Version       : 63.0.3239.108 (Build ufficiale) (a 64 bit) 
URLs (if applicable) :
OS version               : windows 10
Network (such as Cable/DSL/Dial up etc):
Audio/Video format (if applicable): Webm
Special chrome flags (if applicable):

Behavior in Safari (if known):
Behavior in Firefox (if known):

Video issue, Audio issue, both, neither? Audio issue

Flash or HTML5?  HTML5

If the browser or renderer crashed (“Aw, Snap”), please add any crash
IDs from chrome://crashes  (possibly after enabling crash reporting per
http://support.google.com/chrome/bin/answer.py?hl=en&answer=96817)

What steps will reproduce the problem?
(1)opening a random webm on a whichever website
(2)
(3)

What is the expected result? the normal reproduction of the webm

What is the actual result? webm start reproducing but when paused or muted the audio keeps going.

Any additional information (anything else which may help us debug the
issue)? the issue occur on every website but just with Webm, it sound like the Webm start two times, even when i have just one tab open.
Please attach the HTML5/JavaScript code or audio/video files as well as
screenshot and/or videos (if applicable)