Mac is son of as you will know. Out of interest, a woman isn't MacDubhsithe, but is NicDubhsithe, or daughter of. So it is Mr. MacDubhsithe and Mrs. NicDubhsithe.

The pronunciation on the web site is a native speaker, so he can say it way better than me, he is speaking in real time, so it is hard to follow.

I will break it down as best as I can phonetically.

Mac - is not Mac as in MacDonald, in Gaelic that is MACHK the ch as in loch finishing with a hard K. M-A-CH-K

Dubh as in sgian dubh = DOO

sithe = seeye SEE-YE (Ye like??? Yea maybe?

So, all together it is MACHK-DOO SEE-YE.....