This question already has an answer here:
When using emacs, C-S-Backspace seems to only delete one char and not the whole line.
After reading Here I see the text:
"C-S-backspace (kill-whole-line) kills a whole line including its newline, regardless of the position of point within the line. Note that many text terminals will prevent you from typing the key sequence C-S-backspace."
This might explain my problem, but does not give me a solution.
Checking topics like this gives some explanation to possible Ubuntu based issues, but they seem to be GUI based. I'm using the Awesome window manager with the default configs. I don't see anything bound to those keys.
I'm using Ubuntu with Awesome WM. My terminal is XTerm. I'm using emacs 24.3.1.