Can't seem to get any resolution over 2880x1620 to work

[Berke53]

Whatever I try i can't seem to get any resolution over 2880x1620 to work without color compression or reducing refresh rate.
I'm using CRU 1.3 with 2 GTX 1080 GPU's in SLI and a Sony KD55x8509C UHD TV wich both support 4K resolution @ 60hz 4:4:4 chroma.
Reducing refresh rate to 30hz or forcing 4:2:0 chroma subsampling works
So... you would think that the HDMI cable is to long or has poor build quality to transfer the signal correctly.
Well..the weired thing is that 40k 60hz 4:4:4 works perfectly without using the CRU utility. (tested using various chroma subsampling testpaterns) So why does CRU fails to achieve these resolutions?

I would like to set up all resolutions like 1440p, 1620p 1800p and 2160p. Without using CRU i only get standard 1080p, 1440p and 2160p. With the usage of CRU I can get 1080p, 1440p and 1620p but no 1800p and 2160p without color compression. The Standard EDID UHD resolution simply dissapears by using CRU.
I tested the hell out of the CRU application. Putting these resolutions in all possible locations and extention blocks without any result.

Does sombody has any idea what is going on here?

(TV is updated to latest firmware and is set up for enhanced HDMI singnals)

Any help would be greatly appreciated!