I think it has been mentioned by few other people here but I thought would just post this in case any one hasn't seen the previous posts. I have found that if you wipe the cache partition every few days it minimises the amount of times your phone restarts as well make your phone perform better as well. It's definitely worth a try.
You can try to 'wipe cache partition' through the Recovery mode:
1. Turn off your device
2. Connect your device to the PC via USB (not to the charger)
3. Wait until the message that the device is being charged appears
4. Press and hold down the volume up and then power buttons and hold them until the device turns on
5. Recovery menu should appear
6. from there select "Wipe cache partition" (you can navigate using volume up/down buttons and confirm with a power button).