I think I have a lightly used splitter from my previous house. As far as I remember it worked well. I'll try to find it and report back which brand it is.
On a related topic, I have many outlets in my current home (at least 10) and when I went to move the modem and router to another outlet, it wouldn't work. But I believe all outlets work for cable tv. Is there something I need to change in the junction box (which I believe is located in the master closet) to reroute the internet signal?