There are jets and there are air injectors. I am expecting water out of the jets and when I turn the air blower on, I would be expecting air out of the injectors that are there for that purpose. Any water coming out of the could on be the water that back fills the air injector manifold when the blower is turned off.
If you are getting air bubbles out of some identify the ones that are working so that you may point to the ones that don't work when the service person comes out.
If the lines are kinked, plugged, or some how restricted air is not going to come out and this may call for digging into the air injector manifold.
First things first, the next time you are in the Hot Tub (tonight) identify which ones have air bubbles and which ones don't. That will be your starting point.