Cubase limited to 95 midi ports -- not enough

For a few years now, and including the latest version (12.0.52), Cubendo will hang during initialization when a large number of MIDI ports are present. The exact number, I do not know, but any time this happens the only solution has been to reduce the number of active ports somehow-

disable them (by turning off MIDI controllers or virtual ports)
delete them (virtual ports)

Again, I don’t know the exact number that Cubendo allows or handles (or what the mechanism is which limits them), but this has become a major obstacle for maintaining network connections in an advanced MIDI studio, given that communication from programs outside of Cubendo need virtual ports for routing as well as any networked connections.

Cubendo 12.0.52 on Windows 10 pro
Using approximately 90 MIDI ports
Cubendo seems to hang somewhere around 70

Interesting… have you had any luck at all in narrowing down what type of midi port the sequencer gets stuck on?

Presuming that the program is waiting for a response that it doesn’t receive, I would ask what program creates the virtual midi ports, and would try testing launce with each disabled in turn…

I’ve been using loopMIDI for years. The ports will work in Cubendo, until there are too many. Then it hangs on startup.

These ports are recognized properly in other programs and work as expected. If I create too many ports, and go over the invisible Cubendo limit, I can unplug some MIDI controllers and restart Cubendo to get back in (if I have to enough to unplug to get back under that threshold).

At the moment I can count 75 ports appearing and working in Cubendo as “Direct Music” devices.

I just ran a test and found that Cubendo is limiting the the DirectMusic ports to 95. When I add another virtual port while Cubendo is open it will stop responding (freeze) and will be unable to start as well.

If I remove one port (either virtual, or by unplugging a MIDI controller) Cubendo will start back up. This means that the source of the port is not the problem, but the amount of ports present.

Cubendo refuses to process over 95 DirectMusic MIDI ports.
Again, other applications can see these ports fine and are not restrained by them.

Hmm… I am able to load 130 in/out port, so I wonder if the maximum number of ports is a red herring.

I’ve added and subtracted many ports over time and there is no other common attribute than the amount of ports. The name or source of the port does not matter.
Are you using DirectMusic or WinRT?

Of course, DirectMusic. I simply tried to reproduce what happens on your system.

I’m on Windows 11, though. I have not looked to see if there is some change in MIDI-api functions since Win 10.

Given that other programs see and process the ports (Bidule, Dorico, Notion, Divisimate etc.) the issue seems that it must be related to something Cubendo is doing.

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Except for one thing. I cannot repro

Right, but Windows 10 is not creating this problem for other apps.

Righto- so it’s not Windows either.

I think the next troubleshooting step is to eliminate real ports and/or devices as a culprit.

My system has a very simple midi config, 9 physical midi devices, and (at the moment) 130 virtual ports. This is what’s not equal between us – thus my suggestion.

I’ve tried that, even disconnecting my audio interface as well.

Currently there are no devices plugged into the computer other than the mouse/keyboard and screens.

The problem still persists at the exact threshold of 95 ports working, 96 ports not responding.

Also, I should note that it hangs on “Initalizing: Chord Pads” when there are too many ports.

Well, that’s all I got, I’m afraid.

Does it happen when you initialize Cubase? I mean hide the entire pref folder, not safe mode.

Midi ports or midi channels?
I am using a mackie 4 port midi device and can use 4 x 16 midi outs and 4 x 16 midi ins.
No issues.



Utterly random thought - In Windows Device Manager in the View menu select Show hidden devices and then look under Sound, video and game Controllers.

Are there a bunch of faded MIDI ports/devices left over that are perhaps causing an issue?

Noting that you’ve disconnected actual midi devices you have I imagine there will be some real ones that are hidden so be careful not to uninstall those accidentally but you might be able to uninstall some left overs - perhaps they are causing confusion.

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Totally forgot about that mess! Good hunch

Jsut checked mine to make sure I had the instructions right - apparently I have 3x Korg Kronos X - I only need one so I’m gonna sell the other two… :stuck_out_tongue:

Did you guys get this fixed? I’ve got the same issue although I’ve got nowhere near 95 midi ports - what virtualmidi controller are you using? I’m using loopMIDI but only have about 15 devices on it

I did not get this fixed. To this day I still have to limit the MIDI ports any time I start up Cubase/Nuendo. I do use loopMIDI, but that seems to have no bearing on the matter. Any new ports will max out Cubendo. I had to uninstall Divisimate just open Cubendo for a project a few times. Again, this is only an issue in Cubendo. No other MIDI host program is having this problem.