[o2 XDA Flame] The BugDay issue: Flame turns off, sets date and time to 0:00, 1.1.2000

Hello!
Unfortunately I don't know your language, but I really need yours help.
Recently, many Flame (but not all of them) started to turn off and change their date and time to 0:00, 1.1.2000. At the beginning only sometimes, instead of awake from sleep mode, but always more and more frequently. After some time if turn off also while working on it and it ends on that, it turns off even while system start up. I bought another battery and it work for some time, but it's again beginning turning off. A gauge for measuring the amperage says that the internal battery is fine I think...
Some people gave it few times on guarantee to service and finally they somehow fixed it. I don't have guarantee and I was already making jTAG (thx to Medush). It started without any accident form my side and I don't know what to do. I'm sure that it's hardware problem.
Here is xdaflameusers.com topic: http://xdaflameusers.com/viewtopic.php?id=1662
Please help me, I'm counting on you.