Hello everyone!

I have a few racks with S9 antminers. Some racks have 24 miners and other have 18. They are all connected to the internet and hashing, but occasionally one or two machines on each rack will have the red FAULT light on. What I usually do is just shut off the machines, give it 15-20 minutes, and then turn them back on, which normally resolves the issue. But today, every time I turned off a machine, another machine's red light would turn on. I shut off 3 or 4 on each rack and a minute later there are 2 or 3 different machines that now have the red light on. Is there anything I can do to resolve this issue? Does anyone know why this happens? Any help is appreciated.