Instrument installed in auto, car in Aberystwyth (7)
I believe the answer is:
ocarina
'instrument' is the definition.
(ocarina is a kind of instrument)
'installed in auto car in aberystwyth' is the wordplay.
'installed in' says the answer is hidden in the clue.
'OCARINA' is hidden within 'auto car in aberystwyth'.
(Other definitions for ocarina that I've seen before include "toy instrument" , "Play a musical toy in the ICA, Nora" , "Terracotta wind instr." , "Flute-toned musical toy" , "Primitive wind instrument" .)