Focusrite Scarlett 4i4 3rd gen: periodic click on playback

Hello,

I recently purchased a Focusrite Scarlett 4i4 external USB audio card. I am very happy about the audio quality, and recordings are very noiseless.

Unfortunately, during playback, I have a very annoying random click (a sound similar to a elecrostatic discharge, very short and high pitch) every second or so.
That happens :

• with every output, both headphone and speakers,
• on both audio recorded on disk (SSD and HDD) and on live input,
• with either PulseAudio and Jack.
• sometimes louder than others, and sometimes more to the left or to the right

I do not have that issue with my other devices (internal soundcard or graphic card HDMI). I also don't have the issue on Windows. The card is dead silent with no audio playback.

I tried a few things including increasing buffer and periods in Jack, or booting with usbcore.autosuspend=-1, but I can't seem to solve the issue on my own.

I have no idea what to try next (except maybe boot a live CD of some other Linux distro dedicated to music creation). Do you have some?

Thanks.