Enquiry forced changes around a broadcasting channel (5,9)

I believe the answer is:

radio frequency

'broadcasting channel' is the definition.
(frequency for a broadcast)

'enquiry forced changes around a' is the wordplay.
'changes' indicates an anagram.
'around' is an insertion indicator.
'enquiry'+'forced'='enquiryforced'
'enquiryforced' anagrammed gives 'rdiofrequency'.
'rdiofrequency' placed around 'a' is 'RADIO-FREQUENCY'.

I've seen this clue in The Independent.

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