So here is the deal my dash lights go dim when I hit the brakes and come to a stop with headlights, foglights, stereo/subwoofer on then starts idling rough let off the brakes goes back to idling fine after a few seconds l've replaced the battery, alternator, battery terminals, engine grounds tried running without subwoofer on didn't solve anything so I'm all out of ideas any suggestions would help

 

Clean your grounds. Did you replace with a deep cycle battery? You have subs, did you upgrade the charging system? You probably get on that sir.

 

What specific "EK" do you have?

What is the voltage reading across the battery posts with the engine idling and the high beams on?