I wasn't given a lot of info as to what exactly the problem is with V4.4.1 other than the fact that it was why the image uploads were failing. I do know that we are currently running on V4.4.0 so it seemed kind of obvious to me that my host reverted to an earlier version and that solved the problem.
I would contact your host and let them know that this might be causing the problem you are having. I don't know how big a deal it is to revert to an earlier version but it solved the problem we were having.
You might also try Dirk's suggestion in this thread
Sorry I can't be any more specific than this but thats all the info I have.
BTW I checked out your site and think it looks great. What theme are you using and have you made a lot of modifications? I am thinking of refreshing the look of my site and don't recall seeing that theme before.