What you'll notice
The recorder runs (app works, lights on) but the screen reports no signal.
Why it happens
Output resolution above the display's capability, wrong input selected, or a failed cable or port.
How we fix it
We recover the output setting through the app or fallback port, then set a resolution every display on site supports — and label the input so it survives the next remote-control accident.
Still not working?
If the checks above haven't restored your monitor, this usually needs a technician. Our CCTV Repairs service covers exactly this fault.