There is no problem plugging the hub power lead/adapter into the electric power extension. It won't affect your connection
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@licquorice thanks for that , hopefully I’ve tagged you successfully this time 😂
A quick look at an old Type A Smart Hub seems to suggest that the centre pin is 2.5mm, whereas CCTV is generally 2.1mm. So just Google "2.5x5.5mm DC extension cable" & you should find want you need.