monkey - Contact Burton's warranty dept. I have several burton boards and just had something like this on a new 13 Joystick. They have occasional issues with the channel. When the channel is cut apparently and only occasionally, the machines can either dig too deep or be off just enough to cause bubbles, bumps or other odd things.
Weird part was my Joystick was brand new and the bottom was flawless. Only after I waxed it the first time did the bottom bump show. They explained to me the heat from the iron probably exaggerated the problem.
They asked me to email pics in and saw enough to ask me to return it. They sent a brand new replacement back. total turn around time was maybe a week.
Good luck!
Weird part was my Joystick was brand new and the bottom was flawless. Only after I waxed it the first time did the bottom bump show. They explained to me the heat from the iron probably exaggerated the problem.
They asked me to email pics in and saw enough to ask me to return it. They sent a brand new replacement back. total turn around time was maybe a week.
Good luck!