Hi there Pappincole,
Firstly I'd like to welcome you to the forums and say that I'm so sorry to hear that you're set top box won't switch on and is displaying the LD30 error code.
I've done some testing on this for you, and can see some issues that will require a technician to call out, so I'll send you a private message in order to get things moving.
Please look to the top right of this page where you'll see a purple envelope icon, click on this and you'll see my message.
Many thanks and apologies once more.
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