Corsair H100i Platinum SE pump sound

I bought and installed a H100i Platinum SE AIO. The temps I'm seeing seems to be normal as I get around 65C during Cinebench R20 with a Ryzen 3600.

However, the weird thing is that even though overall the AIO is very quiet and as my fans are set to quiet mode. The pump on the other hand makes a weird gurgling/whirring sound. When I change the setting to Quiet mode, there are loud gurgling sounds coming from the pump and is quite loud and constant. If I change the Pump speed to Balanced, then the gurgling sound reduces but it is still there and noticeable. If I change the pump speed to Extreme, this is the quietest as the gurgling sound only occurs once every 10 seconds or so. However, I can hear the humming/whirring sound of the pump at Extreme, but that is still quieter than the gurgling sound of balanced. I don't know if hearing the whirring sound of the pump at Extreme speed (2900rpm) is normal so please let me know for that. As for the gurgling sound, what is that, I can't seem to think that is a perfectly normal sound for the pump to make. Is my AIO faulty? Is there anything I can do to fix this?