I had similar problems only with earlier kernels. Did you remove the battery for any reason? Because in that case you need to re-initialize the real-time clock at OF level. There is a forth script floating around somewhere to fix it, hopefully still available...
I had simular problems on Efika when battery power went low. Replacing by a new battery causes simular problems, as the clock was floating around.
Beside the clock at least on Efika the mac address is also changing to an alternative value.
This is how I fixed it:
1. Remove battery
2. power on and try to set clock.
3. read clock and compare if it's still correct.
4. If the time is now correct, then put (carefully) the battery without shutting down the system. Now problem is solved.
5. if the time is still incorrect, then power down, wait a few minutes, power up and restart with step 2.
This worked for me. Using the system over a month now and the problems are gone and never returned.