1. In Tracktion Waveform 9 all was well, working with the arpeggiator and the Veena sound. But I then turned on the FX, scrolled to the Pitch - Wobbler option in the first space, and dragged the slider on the small FX XY pad. It made a loud pop, and then the main XY Pad on the Seaboard suddenly stopped responding. It actually screwed it up so badly that even using the mouse to drag the main XY pad on the Player screen no longer works. The blue dot just keeps bouncing back to the same spot it's stuck on. Turning the Audio FX off again made/makes no difference. And worse, it corrupted that whole instance of the plugin. I was able to open other songs and load the Studio Player without issue. But even a day later, every time I open that original song, the main XY pad is unresponsive, both to the Seaboard and to the mouse.
2. In Studio One 4 Pro, I was playing with the Bansuri Flute patch with the Smart Chords on. I had the Ambient Slider all the way up, the Attack Layer down, and everything was fine until I slid the Delay slider all the way up. The audio caught and just kept looping (da da da da da...) until I quickly moved all the sliders and XY Pad. Finally it unstuck. I saved the song because I'd been recording at the time. And then to test it, slid the delay all the way up again, hit a note, and immediately it did the same glitch loop, but this time it got jammed so badly that Studio One became unresponsive and I had to force quit.
Those are the two big ones I've found so far. I'll let you know if I run into any major glitches as I use it more.
I've tried to reproduce both your issues but haven't been successful, one quick question I have is whether you're using an external audio interface?
The other thing I can think of, if you're willing, is to send a copy of the Waveform project (feel free to remove anything except for the problem track), that way I can take a look at the issue without having to reproduce it.