I had created a bunch of morphed rigs and used them happily with no issues. I went to make adjustments to them (created in earlier operating system obviously) and was surprised when the values wouldn't change! (yes, I tried this with both the 'Morph Button" On and Off). It's as if they are locked.
I am sure that the connected pedal moved a bit and "moves" the morph state slighty off. For a test, disconnect the morph pedal.