Scenturio
au͘͏͡d̛̀i̛͝a͞ţ͏u͏r ̷͜et ̶͟͝a͡l͜t͢͡͠e͜͠ŗa ͝p͢a̛rs
I can confirm this behaviour on my DM-6.In my experiment all the LFOs have the same duration, if they start together they end together. If they start spread they end spread. And the cycle repeats itself. This is not what one observes, the first cycle is different from the others.
Seems like all Envelopes are triggered directly on keypress no matter in what phase they are currently. If you turn of key sync, everything behaves as expected.
I am not sure if this counts as bug though - one could say that key sync has to ensure that all LFOs have to start new on keypress ... i guess they just did not consider this setup deeply enough.