Rush to make container for mix-tape that had been duplicated? (8)
I believe the answer is:
repeated
'duplicated?' is the definition.
('repeat' can be a synonym of 'duplicate')
'rush to make container for mix-tape that had been' is the wordplay.
I cannot really understand how this works, but
an anagram of 'tape' is 'peat' which is present in the answer.
'rush' could be 'reed' (plants found by water) and 'reed' is found in the leftover letters.
This accounts for all the letters.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for repeated that I've seen before include "Saying again" , "Continual" , "Said again" , "Duplicated" , "Recurring again and again" .)