What is your signal strength and quality like when you go into services, setup, signal test?

Press Services

Select System Setup

Select Signal Test

Sounds like your dish is slighty mis-aligned, dented, the LNB on the end not aligned, skewed or focused correctly, or the LNB has had it.

It could also be a damaged or degrading cable.

I would say your digibox is probably still serviceable and in working order.

You can try tweaking the dish yourself if you want - A tad either way.  The signal strength bar on the TV is delayed, so move and wait.

With a standard region 1 dish (the smaller one) you should be looking for around 3/4 signal strength with a fairly equal quality.  A region 2 dish would give around 90% signal strength.