H80 noise on quite profile

[Braxos]

Hi there
I bought a 550d and a ax860i is comming to town tomorrow. After moving all hardware to the new tower. I had changed the h80 default fan with SP120 high performance but they couldn't be adjusted to the 3 speeds from the pump, quite normal and high speed profiles, so replaced them with the default again. So I used the quite profile to see how quite the rig is. But even at windows desktop on idle as I had used only skype to talk with a friend the system had a irritating noise, so I removed the side door to see where it comes from. After some listening it was the h80 so I stoped for few seconds, with the hand the fans, and the noise was there still so I used the other profiles the noise could only be hiden with the high profile dpeed fans.

Other fans on the tower are
2 front default from the 550d
Xigmatek 602
Asus dc2oc 770

Any ideas what it can be? As I don't think it should be normal since it would make no sense to drop fan speed down if the pump was louder the them.

 

[Topweasel]

Might be a stuck air pocket in the pump on the H80. Just give it a little tap. I have had to do that a total of twice in the last year on mine.

 

[Braxos]

Might be a stuck air pocket in the pump on the H80. Just give it a little tap. I have had to do that a total of twice in the last year on mine.

That was the first I did. Taped fans pump tubes even the frig. But air? How on a closed liquid system!!!??