Well you are not telling us the whole tale sp it is hard to say.
I use stream.print()
So where did this come from?
What baud rate have you got things set to?
It sounds like you have quite a chain of applications, the delay could be in any one of them.
It could be in your arduino code but being the weekend, my crystal ball is stuck at work and I can't get to it.
How about posting the code and describing what you are doing, with links.