How to Fix a Digital Stream DTX9900 HD Converter
Now, taking the removed left side circuit board, use a heated soldering iron to melt the solder away from the two wire connectors at the base of the capacitor (see the two wires dangling from capacitor in the picture to the right?). Then, while the solder is hot and melted, pull out the capacitor with a pliers. Then buy a replacement capacitor.
Here is the Amazon.com replacement capacitor I used: 330uF 16V High Temp Radial Capacitor . Solder the new on in by heating each of the two wires at the base of the capacitor, and holding the solder on the other side of the wire (touching the wire, not the solder), to heat up the solder. When a nice droplet of solder falls into each of the two holes, use a wire cutter to clip off the excess wire. Assemble everything back the way you took it apart and it should work. The green light should not be blinking any more, and it should work as it used to.
link to defective product: http://dtvconverterboxes.blogspot.com/2008/07/digital-stream-dtx9900-review-rating.html
text of the solution at fixya.com that helped me out:
ZorWiz: My (otherwise great...) DTX9900 converter box died with these same symptoms. (Units green LED flashes continuously and unit is dead) My (otherwise great...) DTX9900 converter box died with these same symptoms. (Units green LED flashes continuously and unit is dead). Upon inspecting the unit I located a blown electrolytic capacitor on it's power supply board. After replacing the blown capacitor the converter has worked fine. A blown capacitor can be identified visually. The canister's top will be expanded out instead of flat. Just compare all of the caps. Look for any that are not flat on top. Blown caps will usually be discolored. The bad cap in my unit was a 330uf / 16v - 105c value cap. I replaced it with a slightly superior brand 330uf / 25v - 105c cap.
another corroborating review: http://www.complaintsboard.com/complaints/digital-stream-dtx-9900-c338145.html
how to change capacitors: http://www.tomshardware.com/forum/99446-30-removing-changing-capacitor
fixing the remote buttons: http://dtvconverterboxes.blogspot.com/2009/05/digital-stream-dtx990-owners-manual.html