after update mini pro to 4.0.2.A.0.58 the back button is randomly unresponsive

[#1]

dear all, got a problem here, before today, I am not have any problem what so ever with my xperia mini pro, but today i just upgrade my xperia mini pro SK17i to build number 4.0.2.A.0.58, after this update, my back and menu button begin to be unresponsive or lagged significantly, the backlight of these two button also not turn on.

the responsiveness of home button is not affected at all, so I'm not sure what is the source of the problem here.

for example, let me demonstrate here:

1. unlock my phone - by slide to right > press the corner shortcut - animation is smooth > press the mail icon - open mail and I can imediately scroll down with no lag > press back button...wait up to 3 second and then it go back to home screen or worse it not registered anything, is it like I didnt press the back button

2. unlock my phone - by slide to right > press the corner shortcut - animation is smooth > press the mail icon - open mail and I can imediately scroll down with no lag > press home button - animated smoothly and goes back to home screen

what can make something like this happen? if this is software related action 1 and action 2 should be the same right? this is like some software component after update didn't detect the capacitive button correctly or something.

there is option to repair this phone but it mean that I will loose all things in main memory, I will use this option as the last resort, but for now I would like to hear other opinion about this.

other annoying stuff after this update:

- the APN setting was deleted so I must enter it again

- before update there is mcafee viruscan and mcafee wavesecure, after update it change into mcafee viruscan and mcafee security, and the mcafee security is not compatible with viruscan!! so I must delete viruscan, not that im using it tho, but still.

- there is some carrier spesific app that can be deleted but after boot restart showed up again

[#2]

ok guys, this is my actual condition after I did factory reset to (0.58) on Dec 12, 2011.

the back button can be unresponsive but it is intermittent and the problem can hide for several day before showed up again.

at this moment, I'm pretty sure that the default update (0.58) have a bug, this bug render the software component that handle back button useless (sometime).

I found that this symptom can be detected easily if you turn on haptic feedback in setting>sound>check haptic feedback.... because if the back button become unresponsive there will be no haptic feedback (no vibrate)

if the back button become unresponsive/no haptic feedback, i found that by pressing lock button and unlock it again, the back button will be responsive again. (press lock button to lock and turn off the screen> press again to activate the screen and slide to unlock)

ok guys, hope this can help you all, if you can't use my workaround, my advice will be to downgrade to 2.3.3 by bring it to SE repair center, flash it with clean ROM of 0.58 or just wait for ICS update in march 2012 hoping the bug already fix with the new update

ps:I uninstalled Mcafee after factory reset... no effect whatsoever with this back button problem.

[#3]

Ok guys, yesterday during my flight for business purpose, I completely turn off my xperia mini pro and after I arrived at my destination i turn it on again.

the different is after i turn it on, the OS goes into safe mode (usually it goes to normal mode). i don't know how but maybe because i ocupied with handling my bag and just put my xperia on my pocket and the screen is touching my cloth and somehow activate safe mode.

at that time i don't realize it, but after several day using my phone, the unresponsive back button is GONE! I never experienced it once after the safe mode incident. and this already going on for 2 week.

conclusion:

- safe mode somehow make the service that handle back button responsive again.

question:

- how in the hell i can goes into safe mode again?

regards,

A

[#4]

I think i know how to turn on safe mode. Here you are the:

http://support.verizonwireless.com/clc/devices/knowledge_base.html?id=43067