Criminally corrupt CID tapes dispatch from traveller (7,8)

I believe the answer is:

picture postcard

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'dispatch from traveller' is the definition.
The answer and definition can be both related to communication as well as being singular nouns.
Maybe you can see a link between them that I don't see?

'criminally corrupt cid tapes' is the wordplay.
'criminally' indicates an anagram.
'corrupt'+'cid'+'tapes'='corruptcidtapes'
'corruptcidtapes' with letters rearranged gives 'PICTURE-POSTCARD'.

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I've seen this clue in The Telegraph.

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