What specific settings were changed, from what, to what, between the time it worked and the time it did not?
Knowing those will help determine what setting to change back, and to what.
Without knowing what was changed, I'd just have to guess what kinds of things might have been changed and suggest stuff you can try. However, it is possible to damage the system by changing the wrong things to the wrong values and then using the system in a way that then stresses the hardware because of those settings, so I don't recommend this method.
It is possible that damage has already occurred from the already-done settings changes.
Alternately you can go back to your notes that you made (?) of what all the settings where when you first set it up and got it working, and put all the settings back to those, which will make it work like it did then, if no hardware has been damaged.
If you don't have any of that information, then complete details on your whole system hardware and wiring, and a complete list of all of your settings, might help us help you find the issue.
Also, if anything else happened to the system between the time it worked and the time it didn't, knowing what those things are will also help troubleshoot the problem.
Anything left out of the info provided to us can keep us from being able to help you.
