Nearly all gurgling and leaks are caused by liquid in the airflow, to clear this, flick the device sharply a few times (fig.10), if this does not fix the issue: 

• Coil needs replaced: If the coil is old (more than 7 fills), replace it. 

• Base needs cleaned: Remove and check there is not excess eliquid in it, if so clean out 

If the tank is not gurgling, but leaking (liquid flooding out): 

• Check the coil is screwed in correctly 

• If the leak is coming from around the window, contact customer service. 

• If in doubt, contact customer service.