Nicehash and l3+ with hiveos

so I just got two l3+ with hiveos on them and one of them accepted speed it going from 38 MH/s to about 115 MH/S … SUPER LOW while the other it stable around 300-350 MH/s. the third inhale is running the original software from bitmain and is super stable generally around 420 MH/s.! can anyone suggest why the upgraded software is worse off then bitmains software