DRV8256: Stalling detection

Tool/software:

Hi team my customer is using DRV8256 and they did the stalling test . The problem is that if they set the ITRIP value as 4.16A , the stalling will be detected after around 20s But when the Itrip is set as 7.58A , the stalling will be detected after around 1s. Could u kindly help to explain what is the reason? And when the n fault is triggered when Itrip is set as 7.58A, it seems that even the output has reached the Iocp , the fault is triggered. They can’t understand why. Could u kindly help to give some advice? Thanks 

itrip: 4.16A.  Blue: output current yellow: n fault

Itrip:7.58A