By adding this USB powered variable speed external fan, I was able to lower the operating temperature of the 622 by 29°. Based on before/after average temperature in Counters. I place the fan in the back-left corner where the cabinet vents are, and connected it to the rear USB port for power. On slow speed, the fan cannot be heard, and I'm now able to keep the 622 in the enclosed entertainment center again. The unit is available at many websites, I paid $12.00 + $4.00 shipping for mine.