Eleven in US university cause trouble (3,2)

I believe the answer is:

mix it

'cause trouble' is the definition.
(I've seen this before)

'eleven in us university' is the wordplay.
'eleven' becomes 'xi' (Roman numerals).
'in' is an insertion indicator.
'us university' becomes 'MIT' (Massachusetts Institute of Technology).
'xi' placed into 'mit' is 'MIX IT'.

(Another definition for mix it that I've seen is " Cause trouble".)

I've seen this clue in The Telegraph.

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