Cracking Noise ONLY in Blueray movies

BizzOWND

Hey guys new to this form I am having issues with my sound through my Home theater sound system when and ONLY when I watch blue ray movies... I run a Denon AVR1803 as a receiver (more than 10 years old and what I think may be the problem) Last year bought new Polk Audio Monitor 70 tower Speakers as my Fronts a powered 400w Polk Audio home theater sub Polk Audio Center channel and "no name" backs.. When I am watching Blue ray movies any Special effects sounds my tower speakers send out a "cracking" noise is the best I can describe it.. and this happens at any volume it does not have to be load at all! I thought it was my old fronts so I replaced it with my now Monitor 70s but am having the same result! I can watch a normal DVDs, TV, Music at insane volumes and works perfectly with no ?cracking?. I run 16 Gage wiring to my speakers as well..
Any thoughts?? Please Help!

Serendipity

Are your Front speakers set to "Large" in the Denon? From my experience, I would suggest changing them to "Small", as my Denon AVR-5800 doesn't filter much of the lows (below 20Hz) on movie soundtracks and even Denon recommends all speakers to be set to "Small" for best performance. This will also route the LFE signal away from the mains (yes, it is possible to send LFE to the fronts).