for what its worth I just got my 636 back from repair, becaue it kept turning itself off, some times after only 40 minutes of use. I get it home, and got everything conected and when I ran the room correction program, it gets to the side surround speaker and POP stops working, its off to repair again, I wonder how many times they cobble a fix before I get a refund, I am not happy, this 636 was a replacement for the 608 that melted on us... and we have had this about 6 months