RGBW channel separation ("leakage")

[knuth 28]

I use my RGBWs in input/output mode, specifically to control monocolor LED strips in separate rooms. One room is on the "R" channel, the next on the "G" etc. This mostly works OK. For one of the units I have recently noticed that when the lights are turned on in room 1, the LED strip in room 2 starts glowing ever so faintly. If the LED in room 1 is switched off, the glow goes away. There seems to be insufficient separation between channels, giving a small output on neighboring channels when one channel is in use. The dim level of room 1 is irrelevant - the glow in room 2 is there whenever the room 1 LED is switched on.

 

Another possibly unrelated problem: This particular RGBW controller is on firmware version 25.25. The current version is 26.25, but I have not been able to update it. The new version starts loading, but always stalls at about 50 % progress and then aborts: "Lost connection". Which is strange, as this RGBW unit is the one located closest to the HC2, less than a meter away from it. I have been able to update my other two controllers, located further away, to version 26 using only one or a few attempts. 

 

I don't expect the fw version to play a role in the problem described above. This seems more like a hardware problem. Has anyone experienced something similar? Those of you using the RGBW controller for color control, would not notice. A slight glow of one color when another is activated would not be visible. But those of you using it as a multichannel dimmer could test for the effect I have described. Do you see the same glow?