hey guys

i have a 01 GSR, 67K miles and it runs great when i drive. however, when i turn it off, i hear a crackling noise coming from underneath the IM that make me think i have a hose leaking pressure. now, i never remember hearing this, and when i did hear it, i thought it was b./c i installed a bypass vavle on my CAI, so i thought nothing of it untill my friend said it wasnt the intake. u guys have any ideas what hose this could be? i roughly too a gander under the car but i cant trace the sound to anything. maybe one of you guys have ran into this problem also. if i get a sound recorder, ill try to make a sound clip of the sound so maybe it could be better diagnosed.

TIA
Rob