Same issue. Heavy ping spikes and Packet Loss since last week or so, especially at peak times on Chaos/Ragnarok.
I had a similar issue I think in League of Legends a few years back where the routing through a backbone at peak times caused the latency issues.
This used to be a problem in germany with the ISP "Telekom". The issue was solved by Riot Games.

On which data centers do you guys play?