Here is a link to the terrible clicking sound my High Flow LT makes with flow above 210 l/h (don't forget to turn on the volume). At max flow of 345 l/h it sounds really terrible. The end of the video shows that the sound disappears when I adjust pumps to a flow of 160 l/h.
Please help, or forward to team members for possible fixes.
there is an email adress to join them. that's where customer support will answer.
a copy/paste of your message here, maybe with sales references if you ordered from the website is all you need.
Here it's just a users forum