Prophet 12 arpeggiator latch retriggers off-clock when changing chords - any wor

[Snorre]

I have owned my Prophet 12 for 7 years or so and really love the synth, but I have one thing I dislike. It is the hold/latch functionality especially with the arpeggiator. I would like to be able to lay down a chord on the Prophet letting the ARP run, leaving my hands free to play other instruments. The problem comes when I want to lay down a new chord. When the ARP is in latch mode it retriggers on the key touch rather than playing on the clock pulse. This means that if I'm not super precise the ARP can end up off the grid of everything else that is on the midi-clock. If I have time based delays running it ends up like an even bigger mess.
Have any of you found a way around this behavior?
Hold by itself does not really work as it ends up stacking the chords on top of each other and using a sustain pedal does not work either as it traps all the notes in the sustain part of the envelope.