Subwoofers fades on low frequencies

You keep saying you have a 2000w monoblock. Which amplifier is it? How do you have the subs wired? Does this happen at low volume levels?New Project: 2003 Pathfinder

It is a Starsound SSA-4150 2000 Watt x 4 Channel."when it's too loud, you're too old..."

did you say the low freq is set all the way up? 250htz? try all the way down between 50-80.

I'll ask again. Does this happen at low volumes? Also, how many watts _RMS_ is the amplifier per channel? How do you have it wired? Stop quoting max wattage - it means nothing. My guess is that your amplifier is clipping and you're getting some funky mechanical noise from your woofers instead of bass as it reaches xlim rather than the low notes. New Project: 2003 Pathfinder