Glad you got it sorted out.
The Killer software has been......interesting.....to say the least for quite some time.
Chances are if you install the newest software from the Killer website it will probably work fine , but whatever version most system ship with causes issues non stop for a lot of people. Most of the time it is actually the Wireless that goes flaky instead of the wired.
In almost every case just removing the Killer Software and leaving the driver fixes it.