is that an old battery? I use 3.5A to charge my GP3300, and it won't get very hot. I use 4.5A to charge IB4200, not hot either.
2A is kind of low. BTW, what do you have for the Peak Sensitivity? How many mV? Older Sanyo and GP can only get to 70% of the capacity. 3600 should stop at around 26xx. You have it charged to 30xx, either you discharged too much or your mV too high.