If you're using an Atem switcher with HDMI outputs and you decide to split the output through this HDMI splitter, it might not work. This is not a flaw of this specific HDMI splitter, it's actually a flaw with the Atem switcher. This HDMI splitter, like 99% of the splitters on the market uses Macrosilicon MS9332 chip (I opened it up and checked). Atem for some reason doesn't like this very common chip. (Get a Manhattan compact 4K splitter if you want it to work with Atem!) Otherwise, this splitter works really well, it's reliable and I haven't had any problems with it combining monitors with projectors (other than the aforementioned Atem issue), even connecting a splitter to a splitter!