No signal on Amstrad DRX180

[abu baniaz]

Hi, I am trying to fix an Amstrad DRX180 Sky+ box for a friend.

The fault is that it shows no signal being received, code normally 25 or 30. Oddly, when I check the signal info, both inputs are healthy. On all the channels the EPG is correct and I can also view the ITV channels when I select them.

I have done the following:
Reset the LNB, double check the transponder settings, full system restore, new installation but still no joy. When doing the new install, I get a warning that there's no default transponder. Inputting these again still does not yield anything. I'm certain forced update has not worked as the EPG version is still on 4. Dish and LNB are okay my boxes work fine.

Would I be correct in assuming that this is a PSU fault with incorrect current or voltage going to the LNB? If so, which capacitors do I need to replace?

Many thanks