Could also be airy because of the connection to the device as well. One device, your carto might sit more flush to the device than the other which will allow less air flow to the bottom side of the connection. Check out the connection between the two devices. It might be very miniscule, but will make all the difference in the world..... ie...I have read on occasion when changing from one device to another, some people have had to use a 510-510 connector to get more air flow on another device, when it was too stiff of a draw. In your situation, you might need to plug up one of the air holes on the 510 threads of your carto to lessen up the airiness of your vape.