Hi guys, I have used this forum for ages, but never had much to contribute up until now.
I have a DM800HD, and upon returning to my house one day, the wife said the picture froze and the box wasn't working after a reboot.
as I had an old tuner that would glitch on the HD channels, and as the tuner wasn't showing up in the system menu, I purchased a new glitch free tuner from Ebay.
It arrived, I installed it and had exactly the same problem as before, tuner missing. However, I had noticed that the lcd screen on the unit was pulsing, or fading in and out after bootup, so I took the whole thing apart, re-soldered the power sockets joints and some of the tuner ones, put it all back together again, and still had the problem.
As one last ditch effort, I ordered a new PSU unit from Ebay for about £8, plugged it in, and immediatley noticed that the lcd was no longer pulsing.
As soon as I plugged in the LNB cable, the tuner found stations and started to dceode them. All that waiting and hassle for an £8 PSU unit.
If you have a Missing tuner issue, I would suggest you try this, as it seems there are quite a lot of us out there with the same issue....