First of all welcome to The Astral Pulse!
The reason you couldn't leave was most likely because of the loud music making you focus on the physical. Also the vibrations aren't needed to OBE. Many people don't experience the vibrations and OBE and many people (eg. me) have experienced the vibrations and haven't OBEd.
EDIT: Oh and brainwave generators aren't always a sure to work.
I have a question why is it one time I had the music up loud and was about to have a OBE but I couldn't leave my body I can feel it pulling away, but this time i couldn't even feel any vibrations when it was quiet not either with the help of brainwave files???