H80i Fan maximum speed all the time, won't slow down

Hi guys,



I bought my H80i like 6 months ago, and this issue keep happening, not every time I boost my PC but at least 3-5 times a month.



Here is the problem, I boost my PC, H80i fans go full speed, which is normal, after that the fans slow down a bit then go up to the maximum speed and won't stop.



I used some temperature detect software and found out my CPU is like 70C, but when I touch it at the the back of the motherboard, feels normal. I thought it was the cooling compound problem so at the beginning I usually remove the pump and put some new compound on it, however, doesn't solve the problem, still exist.



Then I start to use corsair link, I found out that every time it happens, the Pump is not detecting by the Link, I think that is the problem since it is "i" series and if the pump was not detected, the temperature of the CPU will goes up (by error, or really went up) and the fan speed will just go maximum.



But, I just don't know how to fix this :(



Does anyone have the same problem? and how to solve this problem permanently? :sigh!:



Thanks