MiamiDX has a few DHCP bugs. One is that it can't renew a permanent lease - it just quits and goes offline with an error message after 20 min or so. So configure your router to set its LAN DHCP lease to 2 weeks or so, if you can - anything but permanent. This bug is also the reason people can't stay online to some ISPs.
If you're using a router, you can safely drop DX. You won't need most of its features, and Miami doesn't have the DHCP bug.
