Choking -- Just started at 8 months old

[Jill]

My son (born with bilateral cleft lip and palate) is 8 1/2 months old now. He has never had a problem eating (formula or solids)until recently. He has just started choking when he is eating solid foods (baby food, cereal). He eats graham crackers very well and as long as I break them into small pieces he doesn't have any problem with choking on them. It just surprises me that he is just now having choking problems. Any thoughts on the subject? Thanks a lot.