Bak Pak 2

[polka]

Just purchased and installed a cpr bak pak2 on my 40 gal f/o. Question is I was under the inpression that it would be quiet. Was I missinformed or should there be some noise?

 

[polka]

I assume that what I am hearing is air noise. Is there anyway to quiet it down? I really notice it when all the kids and husband and the TV have gone to bed. Before I installed this I just had a filter and you didn't hear it at all. Guess I'll have to get used to it. Thanks for your input