Thanks Konflikt for the example! It did help me understand the ‘trigger’ mechanism of the TimerByEvent! Now I’m experimenting along those lines… It seems more stable indeed!
I also noticed something interesting, when I use a fixed FPS of 60 in the general.settings, and play (in window or PIE), looking at the FPS counter, when I look at the drum machines (geometry), it’s sticking at 60 and the tempo is solid, but as soon as I look away, in the ‘void’ (ie no models/no sky), the FPS jumps to 100+ and the tempo slows down (a lot), then I look back at the models, the FPS goes back to 60 and the tempo speeds up as if it’s ‘catching’ up the missed beats… On the other hand, setting the FPS in the settings to smoothed frames, 90-120-60 (60 min, 120 max, 90 smoothed), the tempo is much more solid and looking around / changing geometry count has no impact at all! … Just wonder if you guys know why, one would expect that when it’s at 60, it should stay there, and not change when you have 0 polygons on screen 
I also noticed that adding some delay before everything stabilizes things… Here’s my -very early- prototype:
Anyway, thanks Dan also! Must say that the work you guys have done for UE is fantastic and I can’t wait to dig into the synth side of things (I own quite a bunch of analog synths / making electronic music for nearly 30 years) and was so surprised and happy to see these audio features integrated into a 3d engine - part of what motivates me to learn UE
Thx for the info, though I’m afraid you are talking a little above my -current- brain-grade, lingo-wise, but I understand the general lines you are describing, I have much to learn still!
It sure is a lot of fun! … when I saw these little lites blinking as they should on the beat… Now I just have to learn about programming a multi-sound step sequencer:
Lovin’ UE4!
Cheers,
Nick.