i think the answer is - it depends. Is this new or have you had the problem since you started IP? If you've had it since you started taking the magnesium then cutting down for a bit and seeing what happens probably won't hurt.
If it's new I would suspect a problem with soy or some other ingredient. It looks like you've been OP for about 6 weeks and a lot of people have issues with digesting soy.
Of course, you should always check with your doctor if it persists. I started having problems and thought it was a soy allergy and then a stomach bug. Turns out I had some serious gut problems so a check with your doctor is probably in order.
Started maintenance 05/03/2014
Nothing is impossible. In fact, the word itself says 'I'm Possible'! - Aubrey Hepburn