Hmm, are you taking your blood pressure in the same position as when you get up, without using the binaurals? Some people have bp problems that only happen in certain positions, such as lying down or getting up immediately. If you suspect that the binaural beats are causing bp problems (and not the positional differences), then you should talk to your physician, because this reaction is not normal, and can result from an underlying health problem that the binaural beats are bringing out.
I'm not sure if epilepsy can cause bp anomalies, but binaurals are not recommended with people that have epilepsy or any other type of seizure disorder.