What's the catch??
You maybe think that it is trivial, but it's not. Well yes it is, but there is a mislead in MSDN documentation on MediaElement Position property which states correct format:
"HH:MM:SS" when in fact it necessary to work with
"DD.HH:MM:SS" with 24h+ archives.
Of course the problem is worse because the error it gives away are complete nonsense, like Object don't support that method etc. and it worked for the same file with the same object just a minute ago, or at least before you tried to position before "23:59:59".
So instead of using "83:24:10" use "3.11:24:10" format.
