Download the manual over at ipdb.org. Go to the schematics in the back. I think somewhere in there it will tell you the voltage values you should be reading at the IDC pins on the DMD. Verify you are getting those values and let us know what you find!

Good resource to have. In this case, the OP swapped DMD boards to no effect. This looks to be a voltage issue.

Most of the time. Sometimes, very rarely, the fuse is just old and a small spike in voltage takes a fuse out (we are talking years-old fuses). If you put a new fuse in, and it blows within the week, something isn't right.

Not to overcomplicate things, just a polite piece of advice. If this comes down to desoldering and soldering new pieces in, a desoldering gun should be used to minimize board damage (lifting traces).

Best to either work on a spare board and ensure you know how to properly use a desolder gun, or send it to a professional like Rob (above) or Chris Hibler who both are well qualified to do the job right.

Again, not trying to discourage DIY work, more like issuing friendly advice and make sure your skill sets are ready to do this.

Another option is to buy the Rottendog board as Phat_Jay suggested earlier and sell your old board off for rebuild and keep it alive in the community.

Very niche market and most that are qualified are normally backed up in orders. Another name would be very well welcomed into this community.

Shit. That's a fantastic idea!! Looking at your collection, $400 should be couch cushion change to make this problem go away!