Collapse with cold when having a streak! (4,2)
I believe the answer is:
cave in
'collapse' is the definition.
(cave in is a kind of collapse)
'cold when having a streak' is the wordplay.
'cold' becomes 'c' (eg on taps).
'when having' is a charade indicator (letters next to each other).
'streak' becomes 'vein' (I've seen this before).
'c'+'a'+'vein'='CAVE-IN'
'with' is the link.
(Other definitions for cave in that I've seen before include "Subside, collapse" , "Give way" , "(Roof) collapse; abandon resistance" , "Lose willpower" , "Yield to outside pressure" .)