What's your question? Are you asking if you can get the Dolby Digital repaired? If so, it would probably cost just as much to fix it than to find a used receiver or even buy a new entry level model. You can get a fairly competent receiver for about $200, with DD. One good place to look is Onkyo's website. They have refurbished units for sale that come with a decent warranty. I have seen them under $200 before.
Shinerman.