I found this funny,
My computer, installed my SE as a MSC when I plugged it in and after 4 seconds unplugged it and then replugged it in for the first time.
To switch back to MTP I just deleted the MSC drivers related to the SE and then plugged the SE back in w/o unplugging it and replugging it in.
Haha, it’s funny. But I’m using Vista so I’m not sure if this trick works for XP or such.