they are new filters ? correct? probably just need some break in time ,,,ac70's are pretty quiet ,, prob . not gonna be dead silent like an empty room,, but not noticeable under normal circumstance ,,,I HAVE HEARD OF AC'S NEEDING BREAK IN TIME ,, but I never bought an ac70 new(4 used filters),,, the 2 ac110's I bought took a little time to go silent, one actually started grinding the first day I had it, due to not being "SEATED" properly...I just pulled the motor (pain in the butt) and then pulled the impeller and rinsed it , then re-installed it,, you might try just pulling the impellers and doing the vasoline thing again, eventually new filters will quiet down as the muck from the tank builds up on them and "lubricates "them...