Can’t comment on the BS, but recently got a Sirin as well and have been sequencing from Digitakt, seems to work nicely so far and just wanted to pass on a few “gotchas” I have ran into.
LFO MIDI SYNC - The Sirin’s LFO will sync to MIDI clock by default (you can turn this off through MIDI CC) - So when slaved to the DT, it goes into this sync mode. However, when the DT isn’t playing a pattern, for some reason the Sirin’s LFO stops, or becomes SOOOOO slow that it might as well be stopped, and the LFO rate knob barely does anything. As soon as you hit Play on the DT, things go to normal speeds. So if you have the DT stopped and you’re trying to program a patch on the Sirin and the LFO isn’t working right, that is most likely why. Just send a MIDI command to disable LFO MIDI sync (cc# is in the manual, I forget off hand)
VELOCITY SENSITIVITY - If you want to set velocity levels in the DT sequencer, Sirin is capable of velocity sensitivity to both the filter and amp, but is disabled by default, can be enabled through MIDI CC
PROGRAM CHANGE - When you have a program set on the DT’s MIDI track, every time you hit Play it will reload that preset on the Sirin. So if you are fiddling around with a sound make sure that Program field on the DT is disbled, or make sure to save the preset often on Sirin, or stay on preset #1 (a special preset called Panel Settings that will always match the main panel knob settings) - however, that preset #1 has hidden settings just like all other presets (like whether MIDI sync is on, legato modes, etc.) and THOSE can be saved permanently to the preset, you just can’t save the “front panel” settings as those will always be set to whatever the knobs are. I think that’s the best preset to stay on if doing a lot of fiddling and knob tweaking, then if you settle on something, save it off to a new preset location.
MOD WHEEL INTERACTIONS - This confused me for a while too… When the Sirin boots up, it defaults to using the LFO to VCO and VCF knobs to control the intensity of those modulations. However, as soon as it receives an incoming MOD WHEEL command, those VCO LFO and VCF LFO amounts become “mod wheel amounts”, determining how much the mod wheel affects those parameters, and no longer directly affects the VCO/VCF LFO amounts. So if you send MOD wheel data from the DT (or any other keyboard or sequencer) and then go to tweak those VCO/VCF LFO knobs and things don’t come out as expected, that is why
(took me quite a while to get it working)