We have an Agilent 8453 UV-Vis spectrometer. It appeared that the UV incident light is abnormally weak (huge noise in the UV but normal baseline for Vis in the background scan) compared to the visible region, despite that both the SLS board and UV (deuterium) lamp were very recently replaced. I couldn't come up with other possible causes. Can I have suggestions on which part to troubleshoot? Or can I have suggestions on how to independently verify the UV lamp is working properly, so I can track down other optic components?