One item that really helped me is setting the xsplit server from auto to a server that is closer to me.

Tools -> General Settings -> Channels -> Edit

Change location to something closer to you if you still getting lag or choppy frames. I was losing 100s of frames and now I get occasionally 1 or 2.

I have my settings at Quality 10, VBV 4000 (both) and 32 Khz 16bit stereo at 48000 bitrate. My connection is 35/35 so I can go extreme.