I9500 signal and soft keys not work after update…

Hello, have in my handle one I9500 Eu Version purchased in China, this I9500 had only Network problem first becouse customer have tryed of change *Mei with a Lol APP and them stupid things w/o any knowledge.:mad:

Have tryed of all but Signal was in/out then have Update to 5.0.1 CHN Fw, from this moment "Soft Key Button", dx and sx Home button Stop working!!!

Phone is perfect, BB Ok, Imei OK, all ok, (network now is last problem), but cannot repair this button in touch, reading have seen that isn’t strange this issue but many S4 stop working these Sensor Button after update.

If dgt *#2663# show 2 version of "Phone Touch Key" one 0x10 and below 0x12 if try to update get this error:

IC/s F/W is higher than Bin’s F/W

Have flashed a couple of Fw but still the same, isn’t HW problem becouse NEW Display Not work the same, (have done all test Hw), but have read something here:

and here:

and somedody has solved, but i cannot solving this issue, not want Update to 5.1.1 becouse cannot turn back, (downgrade),

so if anybody here have one solution is welcome