Something odd going on there with Cogent's lines trying to get out of Southern California (not uncommon either--that area has been a hotbed for congestion for a long time now). Looks like there maybe an issue with the load balancing at your hop 9 (154.54.5.65). Testing against it, after about 7 failed pings, it responds from the alternate IP (154.54.12.109). It's almost a repeating pattern too... every 5th to 7th one it responds back on the alternate. It also doesn't resolve the DNS name either.

May want to get in touch with TWC's Tier3 support about this... get some snapshots of both good and bad time frames, and also gather samples of your modem's signal and error logs for submission as well. You can go to their forums and/or twitter for assistance--I've found you wind up getting more progress that way since you can actually get the data to them when contacting them online versus the phone. Ultimately, they should provide you either an email to submit logs and traces and such, or they may direct you to the DSL Reports forum they set up for their reporting. Run some standard traces to your server's IP, as well as some other popular services. See if you can catch samples with those hops responding some times and not at others--pretty good sign they are struggling with congestion through that path. Push them for escalation if you can provide such examples. They will likely make you jump through the hoops of having a tech check your lines and such--they have to work their way through the process so they can push for each escalation. Stick with it and they should eventually get it forwarded to their "engineering" tier, where it will hopefully move forward with routing you around the congested corridor(s) somehow.

It can be done... I've gone through the process here in SC and they've been doing a pretty good job of staying ahead of it so far this year. It took a couple months in 2013 to get the localized nodes split up first (which resolved a lot of other issues), but that left us with the problems still at the peering exchanges. Fortunately, the changes they've been making in the routing to remedy it only takes a few days to put in place at the worst (sometimes it happens the same night). Each time I go back to a previous partner (I regularly get switched amongst TATA, Level3, and Cogent--the PSiNet you are using is affiliated with Cogent), it seems to get a little better. I have particularly noticed I am staying with TATA the longest of the three before it catches up to us. Sign of progress I guess...hopefully it's an indication they are actually finally working to upgrade their peering agreements.