Default [Q] Rooted 2nd Device - Terrible LTE Speeds

I sent my first device in. It was suffering from LTE problems (essentially it would never connect to LTE, and 3g was unusable as well). It's been replaced. The new device seems to be fine. Getting LTE everywhere, when i'm on spark I get up to 25mbps down - great! So I decided to unlock/root the new device. Went through the process, no problems. Now I'm getting terrible LTE speeds. Not more than 60 min ago in the same spot, i was getting 25mbps on LTE, now i'm getting 3mbps after unlocking/root. Any ideas what went wrong?