Serial buffer waits 100ms before letting me "read()" the bytes

[GrindTel]

i have a module transmitting onto a serial line a couple bytes every 15 ms or so. and i need to be able to parse the info, and send back some body data. The problem i'm encountering, is i don't seem to get the data coming in in real time. i get them every 100ms or so. by which time the module i'm working with has moved on with it's life. Almost like i'm getting the data in artificial clumps. I don't see a way to change this behaviour, but i can't imagine that the lower level code has this limitation on it naturally. Any help here would be appreciated.