I know exactly what youre talking about mate. I am experiencing the same thing and using almost identical setup. I'm using ebb and flow with remote reservoir in a sealed grow container that has a constant negative airflow 24/7 through an activated carbon filter.
the flowers get you high, in fact extremely high i might add, but almost no taste or special kick to it. I believe I have limited the possible causes down to two components:
A) It is possible that the exhaust and filtering technology that we are using is so effective that the actual smell that our flowers should have is trapped in the activated carbon filter having been completely sucked out of the plant in a constant negative air pressure environment.