Myrddin

I know someone with this name and it is pronounced Meer-thin. The 'th' is soft, almost like a 'v', and the 'y' is said like 'ear'.

Myrddin - said like "Merlin" only with a smooth "th" instead of L - murthin / mƏrthin - spoken smoothly like "the" or "Mervin", not hard like "earth".