thats really strange. i dont know if the o3 production is subpar, i used to do a search for the synergy here on curezone and most of the users were satisfied. there were just one or two who werent . at least you can smell the ozone, so you know that it produces o3. i ozonate with 11 ug for 2 minutes and its really strong for me.
did you maybe also start with one of those cheap units from china ? then you would have something to compare.