Missing / dropped notes from time to time, how to debug?

Using Zynthian
21

Going a bit crazy over this… Apart from the dropping notes in “busy” compositions, I also seem to get a lot of hanging notes even in simple compositions

Currently have it with only 2 tracks playing.
one plays 3 note chords with Dexed, other plays single notes on Noize Mak3r
The moment I play these together, I almost immediately get hanging notes…
I’m beginning to think there’s perhaps a hardware problem, like optocouplers failing on V5 batch? I don’t know. I just find it weird that I’m having so much problems and not everyone is having them.

CH#04 NOTE_ON 77, Vel: 83
CH#04 NOTE_ON 82, Vel: 112
CH#04 NOTE_ON 84, Vel: 111
CH#06 NOTE_ON 61, Vel: 102
CH#04 NOTE_OFF 77, Vel: 83
CH#04 NOTE_OFF 82, Vel: 112
CH#04 NOTE_OFF 84, Vel: 111
CH#04 NOTE_ON 77, Vel: 83
CH#04 NOTE_ON 82, Vel: 112
CH#04 NOTE_ON 84, Vel: 111
CH#04 NOTE_ON 82, Vel: 112
CH#04 NOTE_OFF 84, Vel: 111
CH#06 NOTE_OFF 61, Vel: 0
CH#06 NOTE_ON 64, Vel: 102
CH#04 NOTE_ON 77, Vel: 83
CH#04 NOTE_ON 82, Vel: 112
CH#04 NOTE_ON 84, Vel: 111
CH#04 NOTE_OFF 77, Vel: 83
CH#04 NOTE_OFF 82, Vel: 112
CH#04 NOTE_OFF 84, Vel: 111
CH#06 NOTE_OFF 64, Vel: 0
CH#06 NOTE_ON 60, Vel: 102
CH#04 NOTE_ON 77, Vel: 83
CH#04 NOTE_ON 82, Vel: 112
CH#04 NOTE_ON 84, Vel: 111
CH#04 NOTE_OFF 77, Vel: 83
CH#04 NOTE_OFF 82, Vel: 112
CH#04 NOTE_OFF 84, Vel: 111
CH#06 NOTE_OFF 60, Vel: 0
CH#04 NOTE_ON 77, Vel: 84
CH#04 NOTE_ON 82, Vel: 111
CH#04 NOTE_ON 84, Vel: 97
CH#06 NOTE_ON 61, Vel: 102
CH#04 NOTE_OFF 77, Vel: 84
CH#04 NOTE_OFF 82, Vel: 111
CH#04 NOTE_OFF 84, Vel: 97
CH#06 NOTE_OFF 61, Vel: 0

I count 20x NOTE_ON in this example, and 17x NOTE_OFF. So there are NOTE_OFFs missing.
I have a ton of other MIDI gear and nowhere do I see any similar issues, so the problem must be either hard or software on the Zynthian.
Was planning on playing live in 2 weeks with the Zynthian as main source of synth sounds. I’m pretty much stressing out about this now :hushed:

Here’s a video displaying the issue with hanging notes:

I’m now going to find my midi interface so I can make some easy to reproduce scenarios for the issue queue…

Being a software engineer in a former life, I guess I will have to dive into the code behind all this if I want to achieve a fix before my gig. Is there some sort of diagram somewhere that gives an overview of how all the components interact with each other? I did check the documentation but I couldn’t find anything like that, so it’s hard to just dive in without a general overview.

22

Hi @rv5
Your video is really good at explaining your issue could you attach a midi file, similar to the video, I wasn’t able to reproduce (from listening ) from your previously attached file.
I tested with both din and USB host.

23

Another example, just playing mutliple notes at same time from MIDI keyboard, usually results in hanging synth (in this case now, ZynAddSubFX)

Midi monitor on Zynthian clearly misses some NOTE_OFFs:

CH#03 NOTE_ON 56, Vel: 74
CH#03 NOTE_ON 68, Vel: 74
CH#03 NOTE_ON 80, Vel: 74
CH#03 NOTE_ON 68, Vel: 77
CH#03 NOTE_ON 80, Vel: 77
CH#03 NOTE_ON 92, Vel: 77
CH#03 NOTE_ON 80, Vel: 43
CH#03 NOTE_OFF 80, Vel: 43
CH#03 NOTE_OFF 92, Vel: 61
CH#03 NOTE_OFF 68, Vel: 61
CH#03 NOTE_OFF 68, Vel: 61

And strange enough: Why is there an extra NOTE_ON on 80? I only played 6 notes. The last NOTE_ON should be a NOTE_OFF, as displayed by the midi monitor on my Hapax:

IMG_3559
IMG_3559600×378 59.2 KB

This adds to my reasoning of data corruption on hardware level

24

Is that on the midi through port

25

no, hapax is in between the Midi KB and the Zynthian

26

Won’t have time to check further in depth today. I’ll make it my mission tomorrow.

27

Midi monitor on Zynthian is the webgui?

28

Yes

29

Okay, good news, sort of…

I could 't find my Midi interface (meh) but I realized the Hapax itself is a Midi interface on its own.
So connected Hapax and Zynthian via USB (Hapax in Device mode) and … ALL ISSUES ARE GONE!!!

So I don’t get any dropped/missing notes at all. Everything is tight. I also never have any hanging notes…

So at least I don’t have to stress any more for my live set, I can just use USB!.
However I do want to investigate this further once I find the time. Especially want to focus on the Midi Through output from Zynthian. I have a gut feeling towards a hardware issue.

30

That’s good news at least, when you find time it would be good if you could produce a midi file similar to the video so that I can test it with my hardware. Since updating mine V5 & V5.1 to staging my issues have gone away.