Question about Philips Hue Play Gradient Lightstrip 55"

I assume that you have wired the whole thing as follows: TV box (Apple TV, Sunrise, Swisscom box or similar) - Hue Sync Box - TV HDMI in? (Because the signal has to come from a TV box, Playstation etc., it doesn't work with TV only)

If so, try a different HDMI output, I'm not sure anymore, but I meant only 2 and 4 work properly. And I also had to change my HDMI cables; I used 8K-capable ones straight away and it's worked perfectly since then.