tweaky virtual faders

when using the virtual faders on the EOS touchscreens as submasters, I pushed the up arrow button to fade up the fader.  but instead of fading up the fader smoothly it did this odd tweaky thing where it would slowly fade up while flickering up and down a few percent.  is this a bug?  it does the same fading down.  the fader works fine if I just touch the virtual handel and slide it up or down.  I'm running version 1.4.1.
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