High ping / jitter when connected through router

[Rattlerskin]

Just recently, I upgraded my Cox cable internet service to the 30 mbps plan but I had a DOCSIS 2.0 modem, so I upgraded to Motorola SB6121 which is running through my Asus RT-N56U router. I previously had no issues with lag in internet gaming, but after this switch it appears as if "something" is going on. My speeds are perfectly fine and have never been better, but speed is only part of the issue. I posted my pingtest.net and speedtest.net results and I really hope someone can provide some input here, because I am by no means a networking guy. Thanks.

Here is a traceroute to yahoo.com

TraceRoute from Network-Tools.com to 98.138.253.109 [yahoo.com]
Hop (ms) (ms) (ms) IP Address Host name
1 39 0 0 206.123.64.42 -
2 0 0 0 173.219.246.92 173-219-246-92-link.sta.suddenlink.net
3 0 0 0 66.76.104.2 66-76-104-2-yahoo.tex.sta.suddenlink.net
4 64 23 64 216.115.96.79 ae-9.pat1.dnx.yahoo.com
5 62 41 41 216.115.100.8 ae-0.pat1.nez.yahoo.com
6 63 42 41 216.115.100.5 xe-7-0-0.msr1.ne1.yahoo.com
7 40 43 41 98.138.144.21 xe-4-0-0.clr1-a-gdc.ne1.yahoo.com
8 39 38 39 98.138.0.91 et-18-25.fab1-1-gdc.ne1.yahoo.com
9 38 64 39 98.138.240.22 po-10.bas2-7-prd.ne1.yahoo.com
10 99 62 62 98.138.253.109 ir1.fp.vip.ne1.yahoo.com
Trace complete

And here is one to google.com

TraceRoute from Network-Tools.com to 74.125.227.1 [google.com]
Hop (ms) (ms) (ms) IP Address Host name
1 0 0 0 8.9.232.73 xe-5-3-0.edge3.dallas1.level3.net
2 Timed out 1 0 4.69.145.12 ae-1-60.edge2.dallas3.level3.net
3 0 0 0 4.59.36.14 google-inc.edge2.dallas3.level3.net
4 0 0 1 72.14.233.65 -
5 1 1 1 216.239.47.54 -
6 0 0 0 74.125.227.1 dfw06s03-in-f1.1e100.net
Trace complete

[Rattlerskin]

And now here are the results when connected directly through the router.

I flashed the router to the newest firmware then unplugged it and tested everything directly through the SB6121. I then power cycled everything again and re-tested while connected through the router. It looks like the issues went away, but I would like someone more competent with networking to take a look at the results.

These are when connected just through the SB6121

TraceRoute from Network-Tools.com to 98.138.253.109 [yahoo.com]
Hop (ms) (ms) (ms) IP Address Host name
1 0 0 0 206.123.64.42 -
2 0 0 0 173.219.246.92 173-219-246-92-link.sta.suddenlink.net
3 0 0 0 66.76.104.2 66-76-104-2-yahoo.tex.sta.suddenlink.net
4 65 23 23 216.115.96.99 ae-5.pat1.che.yahoo.com
5 39 41 40 216.115.96.76 ae-5.pat1.nez.yahoo.com
6 42 40 40 216.115.100.1 xe-5-0-0.msr1.ne1.yahoo.com
7 38 41 37 98.138.0.27 xe-7-0-0.clr2-a-gdc.ne1.yahoo.com
8 39 38 39 98.138.0.81 et-17-1.fab2-1-gdc.ne1.yahoo.com
9 60 38 39 98.138.240.22 po-10.bas2-7-prd.ne1.yahoo.com
10 59 56 47 98.138.253.109 ir1.fp.vip.ne1.yahoo.com
Trace complete


TraceRoute from Network-Tools.com to 74.125.227.5 [google.com]
Hop (ms) (ms) (ms) IP Address Host name
1 0 0 0 8.9.232.73 xe-5-3-0.edge3.dallas1.level3.net
2 0 0 0 4.69.145.76 ae-2-70.edge2.dallas3.level3.net
3 0 0 0 4.59.36.14 google-inc.edge2.dallas3.level3.net
4 0 0 0 72.14.233.65 -
5 0 0 0 216.239.47.54 -
6 0 0 0 74.125.227.5 dfw06s03-in-f5.1e100.net
Trace complete

[Rattlerskin]

And here are the results when connected through the router after FW update of the RT-N56U and a power cycle of both the router and SB6121. Does it look like I am in better shape now, or are there other issues that may still be lurking?