DN4500P Resetting many times a night

I have an issue with my DN4500P modem. It resets several times a night and even a few times during the day. The reset at night is during our heavy usage time and disrupts whatever we are working on. The lights on the front of the modem first an orange light lights on the bottom before all the lights begin flashing and finally going off all together. This will happen at times 3-4 times within an hour to 2 hour period.