Exim

It seems like I'm always having to force flush Exim. I don't know why. Mail gets queued up. I look at the logs. I don't get answers. I do the following and the mail goes out and everything is for for a while:

exim -qff

This is from the Exim man page:

-q[q][i]ff...
    If ff is present, a delivery attempt is forced for every message, 
    whether frozen or not.