that's weird, if the sudden bad latency from computer to router, u may check connection from computer to router first, rather than check latency from router to internet (if the a high ping in LAN, its also affected to WAN/Internet)
1. if using wifi, please test with cat5/cat6 aka LAN cable (the most reliable method..there a quite issue that cause slowdown/jitter/latency in wifi).
2. if the result is the same, may consider a better router (some of the model provided by TMNet is well known by its "performance" )
the even weird is, the latency repeat itself on each 11th ping reply (the ping reply from google is good already, again the problem is the sudden 1 delay ping..periodically)


(edit+add some info)

This post has been edited by rioven: Jun 17 2016, 06:16 AM