Frequent Internet Connection Hiccups

We experience frequent Internet connection hiccups during the day. During the latest interruption, I did speed tests (speedtest.net) and noticed download speeds as low as 12.38 Mbps and as high as 121.16 Mbps. Upload speeds vary from 0.92 Mbps to 5.54 Mbps. The modem connection stats and recent log are attached.

Thanks.