Fix NaN volume levels in HTML5 audio backend
Fix NaN volume levels in HTML5 audio backend

FUSEEProjectTeam/JSIL,mispy/JSIL,volkd/JSIL,TukekeSoft/JSIL,volkd/JSIL,iskiselev/JSIL,x335/JSIL,volkd/JSIL,acourtney2015/JSIL,FUSEEProjectTeam/JSIL,antiufo/JSIL,Trattpingvin/JSIL,hach-que/JSIL,sander-git/JSIL,dmirmilshteyn/JSIL,sander-git/JSIL,sq/JSIL,TukekeSoft/JSIL,sq/JSIL,acourtney2015/JSIL,acourtney2015/JSIL,mispy/JSIL,dmirmilshteyn/JSIL,TukekeSoft/JSIL,volkd/JSIL,hach-que/JSIL,iskiselev/JSIL,Trattpingvin/JSIL,antiufo/JSIL,mispy/JSIL,hach-que/JSIL,sq/JSIL,acourtney2015/JSIL,sander-git/JSIL,FUSEEProjectTeam/JSIL,sander-git/JSIL,hach-que/JSIL,antiufo/JSIL,dmirmilshteyn/JSIL,hach-que/JSIL,Trattpingvin/JSIL,FUSEEProjectTeam/JSIL,TukekeSoft/JSIL,x335/JSIL,acourtney2015/JSIL,iskiselev/JSIL,sq/JSIL,iskiselev/JSIL,sq/JSIL,Trattpingvin/JSIL,x335/JSIL,mispy/JSIL,antiufo/JSIL,iskiselev/JSIL,x335/JSIL,FUSEEProjectTeam/JSIL,sander-git/JSIL,dmirmilshteyn/JSIL,volkd/JSIL