WIZFI201 Hardware EXT_RESET problem

we had to buy some WIZFI210 modules from broker for replacement and have the problem that the EXT_RESET signal is always high and can not be pushed low (only with more than 20mA current). We found that the pcb has a different SOT-23 component connected to this signal. The good pcb´s has a marked SQCF or SQCC component, the bad one have a marked 8ADV component soldered. Exchanging the parts or removing the 8ADV, the EXT_RESET signal works → 8ADV type is not ok.
I think it could be a FET but don´t found a hint in the internet.
Have someone an idea?