Be left inside with record, high-pitched signal (5)
I believe the answer is:
bleep
'high-pitched signal' is the definition.
(I've seen this before)
'be left inside with record' is the wordplay.
'left' becomes 'l' (common abbreviation**).
'inside' means one lot of letters goes inside another.
'with' says to put letters next to each other.
'record' becomes 'ep'.
'be' going around 'l' is 'ble'.
'ble'+'ep'='BLEEP'
(Other definitions for bleep that I've seen before include "warning sound" , "Make short shrill signalling sound" , "Electronic alarm sound" , "Swearing substitute" , "Sharp electronic sound" .)