N300 model C3000 cable modem/router drops internet connection

I have a Netgear N300 C3000 cable modem/router with Time Warner internet service. The modem will stop broadcasting a signal and all internet connection drops from computer, phone, and other devices. The connection is dropped for about 2-5 mins, and this happens about once an hour, although in the past few days it has been starting to happen 2 or 3 times every hour. I have power cycled, reset, switched channels, done pretty much everything I can think of to no avail. I have had Time Warner come out to see if it is something wrong on their end and each time they say its the unit (they did not supply it, I purchased it separately). I have seen similar posts about this. Is there anything I can do? Is the unit defective or does this happen with every unit? Thanks for your help.