You heard /adin/ due to akane --a phenomenon in which written <o> is
pronounced /a/ in certain environments. You may wish to read up on the
languages about which you are making pronouncements.


Richard Wordingham wrote:

It is far less confusing to transliterate than to show the effects of a
strong stress.  In this case, the transliteration is 'odin'.  If you want
to
emphasis that it is a spelling, put it in angle brackets, thus <odin>.  The
pronunciation should be shown between slashes (e.g. /adin/) if it is
phonemic, and in angle bracktes if more detailed, e.g. [V"din].

Hubey:
I've heard it enough times and it always sounds to me like adin, not odin
not that it makes much
difference.