Why does this lady keep saying mh as V when it's surrounded by As? Should this not be pronounced "Snahwen shay" instead of "Snahven shay"?
In some regions, it is always, whether it's slender or broad, but in others, it can be "w" when broad. Depends on dialect
I am from Ulster and was confused by this too - Ulster dialect pretty much always follows broad and slender rules which is why sometimes the name Siobhán here is pronounced 'Shoe-awn'. I personally find it easier to stick to these rules unless I constantly hear it pronounced otherwise! (Eg. Cóbh in Cork - everyone pronounces it as 'cove')