Slow or dropping connection

Well, not sure what it used to be, but your gateway is in Omaha, Nebraska now. You may want to check the weather there when you have a connection problem, just to be sure.

That said, that's just the first thing to check if something's intermittent. The other things that can affect it are:
1. Dish alignment - in case it's been hit hard by something like a lawn mower or falling tree limb, or if the mount has otherwise been somehow dislodged.

2. Blockage and/or reflections - Blowing tree limbs and foliage can cause havoc if anywhere within 45 degrees of the dish's view. The signal can be reflected back into the dish causing nasty standing wave patterns, increasing the overall error rate (and reducing the signal quality number you see).

3. Unsecure cable connections/leaky cables - Cables should be finger tight at the back of the modem as well as at the dish. The cabling itself should be water-resistant, so the outer covering should be clear of any nicks or breaks. Might want to inspect all connections and cabling to make sure there are no problems.
4. Power supply - The modem should be plugged directly into the wall and not go through a filtered power strip or other uninteruptable power source. Power variations and low voltage situations can disrupt the way the modem regulates power to the transmitter through the cabling to the dish.