[Attribute Name] defaultPlaybackRate 1.0 [Additional considerations] A MediaStream is not seekable. Therefore, this attribute MUST always have the value 1.0 and any attempt to alter it MUST fail. [Attribute Type] 
double
D O M S t r i n g
T i m e R a n g e s
u n s i g n e d s h o r t
d o u b l e
u n r e s t r i c t e d d o u b l e
b o o l e a n
D a t e