Hi mate thankyou case arrived this morning just a min ago so many many thanks to you and all who helped resolve my issue. Obviously disregard any other messages left for you with me moaning lol. I am a very happy Corsair customer again at last lol. Cant thank you enough
I'm not really sure if this is a pump issue or fans, but if the noise is somehow dependent to your CPU temp, there is a chance that the fan is culprit. Pump rpm is constant in the H100i, nothing could change that speed because its directly connected to your SATA power. Try unplugging the fans and see if the noise would persist. If this is a fan issue, then It'll be an easier fix vs replacing the whole cooler. I'll have it replaced it via RMA.
I have had my H100i for around 3 months now but it has started to become really loud, I can hear the pump working and its not a consistent hum it's a bit of an on and off drilling noise, also when the CPU gets hot the grinding noise becomes a lot louder. Btw I am not using stock fans I am using the SP120 quiet fans.
What should my course of action be? I ordered the parts through Scan Computers in the UK for your knowledge.