Has-been, by the sound of it, got sack on the first of September when they made bulky, shapeless seats (8)
I believe the answer is:
beanbags
'bulky shapeless seats' is the definition.
The answer and definition can be both man-made objects as well as being plural nouns.
Maybe there's a link between them I don't understand?
'has-been by the sound of it got sack on the first of september when they' is the wordplay.
I cannot quite see how this works, but
'it' could be 'e' ('e' can mean 'electronic' which is similar to 'IT') and 'e' is present in the answer.
'sack' could be 'bag' (I've seen this in another clue) and 'bag' is found in the answer.
'first' could be 'a' (first letter of the alphabet) and 'a' is present in the answer.
This explanation may well be incorrect...
'made' is the link.
Can you help me to learn more?
(Other definitions for beanbags that I've seen before include "Kind of sack-seats filled with plastic granules" , "Soft containers filled with granules and used as seats" , "Large cushion-seats filled with plastic granules" , "Sacks filled with plastic granules, used as seats" , "Large floor cushions filled with polystyrene balls" .)