Criticise terrible roads - shock source of troubles? (8,3)

I believe the answer is:

pandoras jar

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'source of troubles?' is the definition.
I know nothing about this answer so I cannot tell whether this works.

'criticise terrible roads shock' is the wordplay.
'criticise' becomes 'pan' (informal term meaning to criticise heavily).
'terrible' indicates an anagram.
'shock' becomes 'jar' (both can mean to shake).
'roads' with letters rearranged gives 'doras'.
'pan'+'doras'+'jar'='PANDORAS JAR'

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