I just stumbled upon a weird issue when sending midi notes to the Digitone through the Digitakt, where the note release is different depending on whether I have the sequencer running or not.
I have the keystep sending notes on channel 3, which is the channel I have configured on Midi C track of the Digitakt and Track 3 of the Digitone. If I play the keyboard without the sequencer running I get the normal note release, but if I start the sequencer the release is much shorter! What gives? 
Update: the issue doesn’t appear to be related to the Digitakt, it’s the Digitone sequencer that’s causing this behaviour, but I still can’t figure out why… there are no P-locks on that track, it’s completely empty.
I’m having a similar issue too. It’s almost like the release stage of the amp envelope is not working or is being cut way short. I just noticed before bed and will have to trouble shoot tomorrow. Definitely seems sequencer related as it seems to work as expected when sequencer is not running.
I never figured out what was happening, but I did realize it only happened on that specific project so I didn’t bother too much.