Losing connection?

I have been having this problem for awhile. At first, I thought it was just crappy service from Time Warner, but now I am pretty sure that it is the wireless router. It seems like I am constantly losing my internet connection. It seems to mainly happen when I try to connect 2 computers at once. I will lose service for a little bit and then it will come back on and be good for quite awhile. This is really frustrating to put it mildly. I have a N300 Wireless Router. Any suggestions on solving this issue would be greatly appreciated. Thank you!