Help Xperia S freezing!

[Nek0]

Hi everyone.

I'm having a little problem with my Xperia S, it's kind of new (3 weeks of use).
When I'm using the phone normally , everything works great, but if I don't use it for a while and then I try to unlock it, sometimes the phone freezes! Well, not exactly freezing, it still works but VERY slowly, almost like a freeze. I can't turn it off with the power button, I have to use Power + Volume button to turn it off/restart it.

That happened the first week (the phone was unmodified in any way), so I unlocked bootloader and flash it another kernel, and the problem was there.
Later I made a backup of the firmware (6.1.A.2.50) and flashed a custom ROM, and the problem was still there. I reinstalled the original backup firmware and it freezed again.

I relocked the bootloader again and repaired the phone using Sony Update Service, it installed a newer firmware (6.1.A.2.55), and the problem seemed to be gone, but 3 or 4 days later it happened again! -.-

What is causing the cellphone to freeze? Hope someone help me with this. Thanks in advance!
btw, sorry about my english, hope you understand most of what I wrote

 

[Tyseyh]

Take it back for a new handset, you have done everything I can think of.

 

[Nek0]

Take it back for a new handset, you have done everything I can think of.

The only thing I haven't tried yet is to install a non-based stock ROM. Something different than Sony's kernels and firmwares. Maybe I'll give it a try to CyanogenMod. My phone doesn't have warranty now because I unlocked and relocked bootloader.

 

[Tyseyh]

Try it anyway, it shouldn't do that at all.

 

[SacreDro]

Hi guys, I'm new here so I'm gonna ask this in Neko's thread - no offence.
While I was in camera mode -selected the normal camera mode(before it was on SCN Auto) - after that it freezed and restarted the phone. Why is that?

Secondly when I go to "About Phone" i see that Andriod 4.0.4 is installed - I have the Xperia S verion. So from what I know Xperia S comes out with Gingerbread, I don't know why 4.0.4 was already installed.
Another weird this is that when I got to wwwsonymobilecom and selected software update, I didn't get the warning that I have 4.0.4 aldready installed - doesn't 4.0.4 means that I have ICS?
After that I thins that ICS got installed again...odd.

 

[Tyseyh]

Just use SuS or something to reinstall your os. You'll lose everything though

 

[Nek0]

Well, I flashed a custom ROM and a custom Kernel and the freezes are much less than before, still happening (like one time a day or something) but I think I can live with that. Besides, it seems that its getting better with the time, or maybe is my imagination xD

Oh, btw, before I flashed custom ROM and all that stuff, I tried to install CM9 and I get some errors (something about bad blocks in /data and /cache I think), so I wiped and format everything with a custom ICS kernel. I was wondering if that could be the reason of the freezes, but who knows.