We are very aware of this. And back then, also as a result of this, have added support for WDM MIDI drivers in Renoise. Let me try to explain and clear this up a bit. This whole topic is confusing as hell.
The “usual” Windows MIDI drivers, which are still used everywhere (called “MME MIDI”) are based on a technology from the 80s, the multi media implementation of Windows16. Those basically have no support for timestamping, aka applications must somehow try to send out MIDI data in time by their own. This is impossible. How good that works, depends on a shitload of stuff, like the running audio driver, speed of the system, if something else in the system blocks stuff and a lot more. In summary this will always cause a wonky timing. Sometimes more, sometimes less. In overall, using very small audio buffer sizes helps to improve timing. That’s basically the only thing you can do as user.
Steinberg then created new dedicated hardware, to solve this problem (this Midex HW line - Emagic also started building some), which solves this problem by letting the hardware send out MIDI in time, instead of doing this within windows. This is a lot lot more reliable. They also pushed a new MIDI driver standard, DirectMIDI (based on WDM) to be used. This protocol allows timestamping MIDI events: if the hardware supports timestamps, it will take care about the timing. If not, then at least the operating system takes care of the timing, which can do this a lot better than “applications” in general cause it has a more low level access to HW.
We do support those new kind of drivers. They will show up as “Some Name (WDM)” in Renoise. So if you are the lucky owner of a device which is built around this new technology, then this MAY result in better timing. MAY, because its still up to the drivers and HW to do a good or bad job at timing. Especially in the beginning, a lot of those WDM drivers did an even worse job than the old drivers, because, well, it was a kinda new standard. This may have changed over the years.
Summa summarum, with or without “(WDM)” drivers, its really really hard to get reliable MIDI timing on Windows. In any application. And this is not only a Renoise problem. Every music app fights with this on Windows. OSX solved this decades ago already in a neat way. MIDI timing on OSX usually is rarely a problem. There either the drivers use timestamped events. If NOT, the OS does a pretty great job in sending out events in time.
