Haunted HDMI Splitter?

[Darron D]

Several months back a buddy of mine gave me a couple of monitors. One of which was an HP w2338h 23 inch 1080p monitor, for free mind you!  It worked flawlessly for a couple of months, until I tried to use an old rocketfish hdmi splitter on it. After plugging this inglorious little bastard in to my monitor, things were never again so great.  Now the monitor has an odd little quirk where my raspberry pi can display fine over HDMI, but my PC and PS4 are an absolute no go.   What's more is that this same issue occurs on another monitor that the splitter was used on.    I've tried other HDMI cables, no luck. Just want my monitors to work again. Hoping I'm overlooking something here

[Darron D]

Nobody has an answer