I think that pings and trace routes would also be helpful in this situation. Ping and Trace to something like 4.2.2.2 and post the results. Also if you go to 192.168.100.1 in your web browser you should be able to look at the diagnostic information in your modem which could help us as well. We would be looking for the Upstream and Downstream information as well as the SNR (Signal to Noise Ratio). With this information we should be able to determine if it's a problem at your house, or a problem further upstream.
Thanks! If you need any help with getting it just post here and let me know and I will provide detailed directions.
Pinging 4.2.2.2 with 32 bytes of data: Reply from 4.2.2.2: bytes=32 time=27ms TTL=54 Reply from 4.2.2.2: bytes=32 time=61ms TTL=54 Reply from 4.2.2.2: bytes=32 time=43ms TTL=54 Reply from 4.2.2.2: bytes=32 time=137ms TTL=54
Ping statistics for 4.2.2.2: Packets: Sent = 4, Received = 4, Lost = 0 (0% loss), Approximate round trip times in milli-seconds: Minimum = 27ms, Maximum = 137ms, Average = 67ms
C:\Users\Phil>tracert 4.2.2.2
Tracing route to vnsc-bak.sys.gtei.net [4.2.2.2] over a maximum of 30 hops:
1 54 ms 42 ms 9 ms unknown [192.168.1.1] 2 32 ms 45 ms 32 ms 74-140-160-1.dhcp.insightbb.com [74.140.160.1] 3 201 ms 16 ms 270 ms 74-131-0-109.dhcp.insightbb.com [74.131.0.109] 4 790 ms 14 ms 47 ms 74.128.9.241 5 181 ms 258 ms 39 ms sl-gw22-roa-0-0-0.sprintlink.net [144.223.18.41]
6 1100 ms 33 ms 111 ms sl-crs1-roa-1-12-2-0.sprintlink.net [144.232.5.1 07] 7 184 ms 129 ms 33 ms sl-crs1-roa-0-2-2-0.sprintlink.net [144.232.18.3 6] 8 94 ms 86 ms 26 ms sl-st20-chi-13-0-0.sprintlink.net [144.232.20.3]
9 33 ms 19 ms 19 ms 144.232.8.114 10 * 249 ms 887 ms ae-11-51.car1.Chicago1.Level3.net [4.68.101.2] 11 71 ms 163 ms 32 ms vnsc-bak.sys.gtei.net [4.2.2.2]
Hmm there should be no reason you would get 50 ms to your router as seen in that trace. Is this over WiFi? Makes me think maybe the problem could be inside your network. Have you rebooted everything (PC, router, modem)? Are you running torrents, etc?