I also did an exchange and this solved the sparkles and heat problem. Now I'm down to the audio drop out issue. Please let me know if the optical out on your unit has a steady output. I also found that WPIX in New York started transmitting on their DTV channel and my DST50 does not output any audio when this channel is selected. My RCA DCT100 gets the audio with no problem. The good old economical RCA is still king of the STB when it comes to overall performance. Too bad it doesn't have the recording capability.