I've been using 3800D for 7 years (disabled standby mode, ie., always on) and it still works. Encountered system hang from time to time during the first year. The problem was resolved after installing a laptop cooler pad (with fan) and running at 24/7.
I've no idea about 9600D. System hang could be caused by various factors. However, overheat is a common issue of magictv devices.