Frequent disconnects and periods of high latency

For the past 2 weeks, I have been having frequent periods where I experience audio dropouts during meetings and delays while working on remote computers.  At similar times my router will log a period of high latency. Between 1 and 3 times per day it also reports that the ISP has disconnected. I have restarted both the modem and router multiple times, either separately or together.

I have a program that pings an external server every few seconds running on a computer connected to the modem that also reports connection trouble at similar times.  This makes me think that the problem is not in the router. 

I have an Arris G34 G36 modem and Unifi Dream Router.

What can I do to resolve this connection problem?