TekSavvy → [Cable] Anyone seeing uber slow streaming issues?

I'm on the 150 connection and for the last few days I've had nothing but headache streaming via YouTube or even through my XBOX ONE console. Just watching a preview video for upcoming games forces buffering every 15 seconds. Up until this point things have been great, but this is absolute madness. I can't watch a YouTube video set higher than 480p without constant stop and start spooling. Speedtest results look fine (Ping, Up and Down are excellent). I'm in the Brooklin area just North of Whitby.