Latency Spikes every 15 secs Australian Server

Hi Guys,

having trouble with lag spikes for the last 2 weeks, every 10-15 secs it will peak to 400-500 ms then return to 30-50 ms and do this in any instance (Hideout, map, rouge harbour)




I've followed a few tutorials on Youtube to help but this didn't resolve anything.
https://www.youtube.com/watch?v=WvI3O6_lcjA

Anyone have any ideas what i can do league is amazing but i cant play like this.