Signal Through Splitter Different on Two Projectors?

[JJackson]

This is a weird one. I've got a mac mini M1 that's connected to two displays. One goes to an extender, which goes to a splitter, which goes to two Panasonic DW740 projectors. The HDMI goes straight to the extender, while thunderbolt is used to go to a second monitor. 

 

So here's the symptom: one projector presents the image green-shifted. Or, the other projector presents the image green-shifted. Almost always green shifted. 

 

Here's our solution: trial and error, we eventually just tried running through the thunderbolt dingle instead of HDMI, and now the projectors are presenting whatever image correctly. Now the other monitor is occasionally presenting wonky colors. So the problem has to be the mac mini's HDMI.

 

So here's my question: how can a signal coming from HDMI to two projectors over a splitter, fail to display the same thing on both projectors? I would expect both projectors to display the same wonky image - not one to display correctly and the other incorrectly. We don't really need help, the issue is resolved - both projectors are now displaying properly. I'm just wondering if anyone knows why this kind of thing would happen?

[Kilrah]

Green shifts are usually poor signal quality. What splitter is that? If it's not active the signal probably becomes just bad enough for one to not lock onto it correctly.