MIDI Remote Control - Hardware fader moves previous selected fader as well

After I create my MIDI remote control for my Arturia Keylab 88 this morning, I tested the fader assignment of the “selected” channel. As soon as I move the fader on the next selected channel, the previous fader moves as well with a slight amount. This never happened when the MIDI remote control first launched…
See attached GIF.
Fader Issue 01

Hi,

To me it looks like the very 1st MIDI Message after the track switch passes to the originaly selected track.

So how do I keep track of this issue as it’s getting fixed?