Paradigm DSP-3200 Help

Hey guys I have a Paradigm DSP-3200 and recently at certain frequencies or low bass I am starting to hear little pops now and then!! Now I did have it sent back to Paradigm for "testing" and they have told me they have found no issues at all! Well it never used to do this and I am still hearing pops! The sub still sounds amazing just certain frequencies the pops happen.

Any insight on what the issue is or is my sub blown???

???

No that's whats sort of weird....my volume is set about a little more than half! Most of the time it is when there is alot of bass....almost like it cant produce those certain frequencies and starts to pop a bit. It still sounds good most of the time.....just wondering if its pretty much on its way to being blown?????

My sub cutoff is 80hz and my volume on the sub is pretty much half. My sub level is at -3db as well on my receiver.