I9100 power key problem

[tzitzu]

Hello all i got in service an i9100 with not water but wine damage reported, initial tested problems was : short batery life , when making cals it does but on speaker directly , random aplication opening , fake all most not charging, when i've inserted the batery phone automaticaly powers on and imei sometimes its 00046.... sometimes its normal 358...
after opening , board has no liquid contact signs, was all clear stock only signs of wine damages was , earphones jack plug , lock/on-off switch, and micro usb board . i've flash it with stock firmware, not moded or , pached or other kind of third party firmwares , changed the jack plug flex cable to fix the speacker problem , and changed the micro usb board with a brand new one. So now the main problem is the on -off /lock buton whats actualy works bad . could it be from the usb board i replaced it (beeing new maybe is broken from factory) or could be some other problem ?
b.r.