LOL, I had this same issue and it took me MONTHS to figure it out. I thought I had a leak for the longest time and I even tried to use shaving cream to find the suction leak.
But yes, you will see small constant bubbles from SWG AND my bubbles didn't go away right after shutting off the SWG (which is why I didn't associate the bubbles to the SWG when troubleshooting "the leak"). Now that you know what they are and depending on the settings of the SWG (mine is turned down low), you will see them come and go as the SWG turns on and off.