MIDI input events random latency (not audio output, that works fine, using ASIO already, thx)


I’ve got an USB-incapable MIDI controller (Elka Mk88 with poly touch, that’s why it’s worth it) whose MIDI din output is hooked up by both-end-MIDI-din cable to the MIDI din input of a Steinberg UR22C interface. I’m using Cubase 11 under Windows 10. I’m regularly experiencing on certain notes (or more precisely MIDI events, note on, note off, etc), but not all, a random latency. If I trill a C3, the two first might well sound immediately, but the third might have a latency of between let’s say half to a full second. The same goes with simple chords, one might be perfect and the next late or not all notes together although I pressed them simultaneously. There seems to be some kind of overflow. It makes it practically impossible to use the integrated PCM player (Halion) to play a piano reliably for example.

To eliminate possible culprits, the following additional facts have been tested:

  • Playing the MIDI controller by MIDI din cable with an actual synth directly (Hydrasynth for example) never shows any latency. As a result, the MIDI controller is not the problem, nor the cable (well it would have been hard, but now it’s sure).
  • Playing a sequence in Cubase with the integrated PCM player (through, of course, ASIO drivers) never shows any audible latency and the same with external physical synths (About not using the ASIO drivers, the latency you’d witness is usually consistent for all notes, not random, i.e. it’s a fixed latency due to the bad speed of other drivers than Steinberg’s ASIO, but how it’s bad is constant, so that you can work around this by applying a negative offset on MIDI events when playing back the sequence). So the driver settings is not the culprit as well.
  • The virtual keyboard (ALT-K) of Cubase does not show any latency.
  • With the external MIDI controller, some notes are recorded at the wrong time, but not all of them.
  • Additional note: the advent of accidentally sending poly touch events on a Mk88 is infinitesimal, as it’s a really hard to trigger aftertouch (not like the one of the Hydrasynth that is easy and allows easy expressivelness). That is not the culprit here. Indeed, I almost have to sit on a key to get aftertouch to my disarray. The other side of the coin is that hitting hard a key or a chord does not generate such events (that would otherwise be recorded anyway), which is good for a piano-style keyboard.

As a result, I think we may now conclude that the problem lies between the MIDI din input of the UR22C and Cubase MIDI input end of routing to tracks, or even just limited to the interface and its driver depending on how the virtual keyboards MIDI events are routed internally (but don’t show the issue).

Would you know what would cause such random MIDI input event latencies (again not latency in playing back sounds, I do, of course, use ASIO drivers)? Would you have guidelines on what to check on Windows that might impede MIDI reliability? Would you have a cookbook on how to eliminate such issues (change some process priorities if that helps, not so sure…)? Would you need more information?

Thanks in advance. Regards.