Pops and clicks could come from various sources of problems.
In a first steps i would recommend unplug / replug everything
In S1 make sure you selected the good audio interface and that the buffer size is high if you process audio or low if you record some .
If you just playback & process some loops & sample you can go for 1024 .
Also there is an anti-droppout protection that you can set to high.
When you are playing and hearing clicks /pops , are you performances meters at the bottom left displaying a high activity or not at all ?
Is it happening on any projects ? did you considered updating at least to 3.5 , i know there is some majors fixes between 3.0 / 3.1 and 3.5.
Hope this might help;
Kind regards .