Hello Jamriman, welcome to NST.
EasyBCD isn't the source of your problem. It
fixes problems, not causes them, usually.

It sounds like your problem could be having the wrong HDD first (most likely OS X's) in the boot sequence in your BIOS (accessed by F2, Del, or a similar key when seeing the first splash screen when starting your computer; it should show you what key you need you need to press to enter the BIOS). Check that first, and if it solves the problem, then great. Otherwise, post back if it turns out that is not the issue, and it is something else.