A few days ago, the phone got an OTA update (build number: IMM76D.I9300XXALF6). After that the phone got unusable: Once the screen goes out, I cannot wake up the device anymore. The only exception is when it's connected to my laptop, then I can wake it up any time.
I already tried resetting it to factory defaults, but it did not help.
Any ideas? Or should I send the phone back?