Pax feedback to staff (CCK) loud discharge sound at rear DT car. Staff (BBT) checked and confirmed -Rear DT car B1 train door has air discharge sound. Train do or was able to open and close normally. MR was 10 bar. Fault ~~~~~ 3621 Pax feedback to staff (CCK) loud discharge sound at rear DT car. Staff (BBT) checked and confirmed -Rear DT(3622) car B1 train door has air discharge sound. Train door was able to open and close normally. MR was 10 bar. Fault self-cleared departing station. CE:T414(3621) Check n found this car B1 door having air seepage sound. Sounds occurs only when train propel the first initial 10sec. MR pressure 10. No other abnormality found during monitoring. Observed air seepage occur on the trailing DT car.  found #3622 A/S WFL air hose burst cause heavy air discharge sound. Replace air hose and metal adapter and function test ok. B1 door check no abnormal noise. Done By:Jack/Koh/Rizman Date:02/11/2023