Firstly I'd like to welcome you to the forums and say that I'm sorry to hear that strange noises are coming from your set top box.
I'm unable to send a replacement power lead, so would like to arrange for a technician to call out and take a look at things for you.
I've sent you a private message in order to get things moving with this, 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 again,
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