You can use PowerShell’s -split operator which uses regular expressions.
"Video Video Audio Audio VBI VBI" -split '\s+'
As noted by @StijnDeVos, this does not remove leading/trailing whitespace.
Here, the \s represents whitespace characters, and the + matches one or more of them. All the more reason to go with @user3554001’s answer.
Another option is to filter the empty strings.
"Video Video Audio Audio VBI VBI".split()| where {$_}