I am a newbie. I have had this Denon 2809CI for some time now. But, when I play it loud it will shut down in 5-10 mins. Since new. I have Deftek BP7006 front, Deftek BP2002 center, and Deftek BP (?) 2004?:blink: ( bookshelf ) can not find the model# on them. I am looking at upgrading to a Denon 4520 or 3313. Any suggestions? Or something that can drive these speakers like they are meant to be?