Issue sending MIDI CC via envelope automation

[GdabZ]

Hello,

What I want to do:
I try to send MIDI CC to an external synth (a Korg Minilogue).
I'm using a pair of MIDI and Audio tracks (dubbed "Method 2" - https://help.ableton.com/hc/en-us/artic ... -with-Live)
I have only one clip, containing a note and an envelope (Pitch):



The setup:
I'm using Live 9.4.7 on Windows 10, with a Focusrite 18i8. Latency is OK, CPU is at 1%. The Korg Minilogue receives its MIDI signals via USB.
My computer: I7 4790K, 16Go DDR3, SSD 1To

THE ISSUE:
The pitch is jittery. I have audible stepping where there should be none. Sometimes the automation works, sometimes it doesn't (the pitch doesn't follow correctly, stays up, stays down, etc.). It is even worse when Live is not the main selected window, i.e. when I browse the web with Chrome on top of Live. The pitch staying up or down indicates that it's not just a delay issue, but that all CC messages aren't sent.

What I have tried:
_ Using another external synth (Moog Sub37, over USB). I have the same issue, so it's not the Minilogue.
_ Using a MacBook Pro with the same project/synth/soundcard. I then have no issue. But this is not an option for me. So this indicates a Windows only issue.
_ Using the same pitch envelope on an Operator synth (soft synth). It works, but then again... It just shows that the problem is not Live that doesn't follow its automation curve, but probably more that it is not sending all the MIDI CC messages it should.
_ Using FL Studio or NI Maschine: no issue. So it's not an issue with MIDI over USB system-wise. It's an Ableton Live issue.
_ Using FL Studio as a VST to send the automation envelope to FL which then communicates to the Minilogue and then get the audio signal back in Live. IT WORKS! But it is preposterous. But as for the Operator test, it shows that Live has no issue with reading the curve itself, but more with sending MIDI messages.
_ Using another audio interface (RME Babyface). Same issue, so it's not the Focusrite.
_ Increase the asio driver buffer size. Curiously it works (a 1024 samples buffer will produce a better automation) but it's not perfect, and I need low latency so this is not an option.
_ Using "High performance" power plan. No difference.
_ Tweaking Live thread priority to "High" and "Realtime". No difference.
_ Using all compatibility modes, from Win8 to Vista. No difference.

I've read that some people have had this issue in the past:
- viewtopic.php?f=1&t=210088&view=next

But there seem to be no solution for me to this day. I'm all out of tests so I could really use some help.

Thanks!

TL/DR
I have a Windows issue with Live 9 not sending automation envelopes correctly via MIDI over USB to external synths.

[GdabZ]

What I still have to try:
_ See if "Reduced Latency when Monitoring" changes anything.
_ Using "External Instrument" instead of using a pair of MIDI and Audio tracks
_ Tweaking Options.txt, I've read on some forum that there were several options regarding MIDI operation, that are unfortunately undocumented:
MidiEventThinning
MidiJitterLogging
MidiEditorDefaultSnapMode
MidiRemoteScriptsFolder
NoMidiFromReWire
NoMidiEventFiltering
NoMidiJitterCorrection
NoMidiMonitorLatencyCompensation
NoMidiServer

Will try tonight. I will keep you posted.

[[jur]]

You said that increasing your buffer works. 1024 is obviously way too high for performance, but what buffer size do you usually use?
Your issue looks very tricky. You should contact support@ableton.com

[GdabZ]

My buffer size is usually around 128 samples or lower. Audio works fine, with no glitches.

It's really just a MIDI issue where all messages are not sent towards external synths. I've contacted the support, I will wait for their answer and post there if it helped.

[GdabZ]

For reference I made a listenable example.

The pitch curve:


When the pitch curve is correctly sent to the device, it sounds like:
https://vocaroo.com/i/s1y2hTKbTtL0

When the pitch curve f*cks up, it sounds like:
https://vocaroo.com/i/s1Eq8mk8ZeS5

[GdabZ]

Tonight I tried:
_ Checking "Reduced Latency when Monitoring" with my pair of MIDI and Audio tracks, and adjusting the delay compensation of the track. Does nothing (it does introduce a delay but the automation is still glitchy).
_ Using "External Instrument" instead of using a pair of MIDI and Audio tracks. Not much better (recorded sample in previous post was made with that method).
_ Unplugging my fancy ass gaming mouse as I thought it could disturb USB with its high polling frequency. Does nothing.
_ Unplugging my fancy ass gaming keyboard too. Same. Des nothing. At that point nothing but the Minilogue, the Focusrite and a not so fancy lambda keyboard were USB connected to my computer.

I haven't tried the Options.txt stuff because it's not documented and also I'm starting to feel a little hopeless, too.

[GdabZ]

Tonight I tried:
_ Disabling Display Scaling in OS Display Settings (I usually run at 150% on my 2580x1440 monitor), so that I could uncheck a compatibility option for Live ("Override high DPI scaling behavior", I thought Windows may behave differently if a compatibility option is enabled). Everything is now so small my eyes hurt. But no improvement regarding my issue.
_ Using a real MIDI cable instead of MIDI over USB. The MIDI cable is still connected to the Focusrite which is connected... in USB. But let's try everything. That one cost me 5€, I will survive though. No improvement detected.

All out of tests again.

The only thing that improves MIDI behavior consistently is having a 512 or 1024 samples buffer. I don't really understand why. With a 64 samples buffer, CPU is at 2%, with a 1024 samples buffer, CPU is at 0%. Seems like there's enough room to send MIDI messages. I've got an I7 4790K. That's up to 4.40ghz of raw power. This makes no sense. It's as if Live process was on ultra low priority (even when I manually set it to high priority in the Task Manager).

[GdabZ]

For those who wonder, the support today confirmed that they were able to reproduce this issue with Windows 10 and Live 9.7.4.

Will keep you posted if the issue is solved. Shouldn't affect anyone as I'm apparently the only one using Live on Windows with external synths.

[miyaru]

No you are not the only one using external synths, I use two of them: a Korg R3 connected by USB and a Korg N1 connected using midi cables and a TIE 1I1O midi controller.

This weekend I will do some tests as I am on Win 10 Pro too and also Live Suite 9.7.4

[GdabZ]

Cool, thanks man! The support was able to confirm that increasing the buffer size > 256 samples fixed the issue, but they don't seem to know for sure why for now.

[miyaru]

Normally, I run Live @ 512 samples, but will test it at lower settings for you.....

[miyaru]

I tested @ 64 samples - audio cracked sometimes, but midi was tight and not glitchy. Used both midi over USB and midi over the TIE 1i1o controller via cables. I think midi over a Focusrite isn't very good, but it must do the job with a simple envelope.

I think it is a strange phenomina, and Ableton must work on it, as we are not the only ones using hardware synths these days.

Midi over USB should not be a problem as the bandwith of midi is so small, USB can cope with it easely, I used to run 4 synths over an USB interface (MOTU MIDI Timepiece AV) without a problem.

And yes, I have drawn the envelope with straight lines, just as you did.....

Not much of help, but we know now it can work @ 64 samples......

[GdabZ]

Hello !

Thanks for taking the time to test.

It's weird, we've got similar configurations, we should see similar results.

My config:
_ I7 4790K 4.3Ghz
_ 16 Go DDR3 1600
_ 1.5To SSD (Samsung 850 & 840 Evo)
_ GeForce GTX 1070, with Gsync enabled (only in fullscreen-mode though, so I doubt there's any interaction with Live there)
_ Random gaming mouse & keyboard, but as I said before, I tested without too with no change
_ Windows 10 (up to date with the Creators Update)
_ Focusrite Scarlett 18i8

What's in your rig that is not in mine? or vice versa?

[snakedogman]

Cool, thanks man! The support was able to confirm that increasing the buffer size > 256 samples fixed the issue, but they don't seem to know for sure why for now.

Yeah I had this issue before and Ableton support never really managed to figure out what the problem was. They were able to reproduce it on one old machine with the difference that chaning the buffer size didn't affect the behaviour there. Changing the buffer did affect the problem for me. As far as I remember buffer of 512 or above made the problem go away for me. I could reproduce the issue on two different computers with two different interfaces (one running Scope PCI cards and one running Focusrite Sapphire), so it was really strange Ableton couldn't reproduce it or figure out what the issue was.

[miyaru]

I remember that clocking to a device can cause problems. By this I mean sent a clock signal to a synth for it's arpergiator or so to be in time with the music. This causes loads of data on the midi line maybe.....

Try to unclock and see what happens!