poor streaming fps

Can't seem to find any information on this issue. My system is an i7 2600k (4.2ghz), GTX 770 4gb, 16gb ram, Windows 7 x64. I stream most other games just fine, but for some reason while streaming FFXIV, my _stream_ fps drops to 13-17. I have messed with OBS settings, in-game graphics settings, fullscreen/windowed mode. Nothing seems to help.

OBS Settings:
x264, CBR, CBR padding, 2500kbps (reduced from 3500), 720p (reso downgrade) @ 30 fps, aero disabled

Again, the stream is what's laggy, my game runs just fine @ 50+ fps. I hardly notice any fps drop in game. Any ideas on what might be causing this issue?