Yes I had the same experience, which actually makes using a default snapshot to reset the routing to the correct one on startup, and after this loading a more complex snapshot impossible, because my zynthian now freezes upon trying to change of snapshot. The only workeable and so far reliable workaround I have now is to make a default snapshot in which the whole setup is finished, except the reverb and delay plugin, and adding those manually each time after booting up the Zynthian. I think it has to do with the fact that the delay and reverb both come after the AMS mixer plugins, and they have to be added in serial at the end of the chain, for all the parallel mixer plugins to be routed to it simultaniously. This seems to be something the Zynthian does not like. So keeping the snapshot without those fx plugins works, and I can also keep all midi mappings so I don’t have to set those up each time. The only problem is that this way it is not possible to save specific delay/reverb settings for individual songs, which will be problematic when using this setup during a stressful live performance. For the sounds and levels this is OK as I send those via program changes externally for each song anyway from my Squarp Pyramid and I only plan on using a bunch of Fluidsynths and the external audio inputs.
My problems with the Zynthian also kept increasing the more I tried to use the aux routing method. I decided to attempt something similar without using auxes, just using two FX plugin added to each instrument layer, but even this seems to not be fully stored in the snapshots. I’ve had random problems like one fluidsynth suddenly only being on the left channel, despite panning being in the center and both outputs selected in the output routing. Also some FX randomly turned off, sometimes the first effect in the chain, sometimes the second. I never used more than two effects on a layer (reverb and delay). I assumed this method is supposed to be more reliable, but maybe my routing experimentations permanently changed the behaviour of the zynthian? It also freezes now when I try to reboot via the admin screen, forcing me to cut the power and reboot this way. Tomorrow I’ll try to format the SD card and install the prepared zynthian disk image again. If I’m still having problems I’m assuming it’s my SD card, as it’s the only part that was not part of the kit… Here’s the snapshot I was using now: 001-JV;Gain.zss (53.4 KB)
Apologies for not being very active recently, been stupidly busy with work, but am slowly acquiring things I could pick up locally (some on loan from friends), pulling it all together, and trying to get my skills and coordination up to speed.
I have to say, after seeing everything I was using mapped out physically on a mixer like this I can understand why the Zynthian might have been struggling under the load!
Of course the flexibility with inputs for other devices I now have would have been impossible on the Zynthian, but physical effects pedals and the per channel EQ and compression on the mixer have replaced internal effects and utility layers on the Zynthian, so almost everything you see here I was at least trying to do on the Zynthian.
All of this gear is a bit ridiculous for someone of my capacity, but it works in a way I can get my head around, and (when I get the chance to play) I’m having an absolute great time doing it.
Having hands on controls mapped out visually is something I didn’t know I would need so much. Flipping between channels on a MIDI controller and screens on the Zynthian whilst trying to get everything else right was too much for my feeble mind. Having everything immediately accessible, and organised visually in rows is still a lot to get used to, but I’m getting there slowly.
Aside from the cost and space requirements in my living room the only real downside so far is that I can’t save ‘presets’ for a setup like this except by taking photos like the one attached, as there’s obviously no way to otherwise recall the position of all the knobs and sliders.
And, don’t worry! The Zynthian is still being used in a variety of different ways. It is almost always sequencing something, and has been put to use as filter/effect unit, sample player, lead/bass synth, percussion, MIDI router, and more beyond. I’m also considering an external soundcard with more inputs and outputs so I can make even better use of it. This may have to be a little further down the track tho, it’s near impossible to get decent components where I live, and shipping is unreliable and very expensive.
Only because I promised earlier, but here is my humble 
. It’s the nearest I’ve managed to something I like, but I must remind you I’m neither musician nor sound technician haha. Anyway:
Like I said I’m still very much trying to get my skills and coordination up to scratch with all this, so there’s nowhere near as much manual automation as I would like. Hopefully I’ll get better at the subtleties and can learn to better tie everything together. It’s fun practicing tho!
Thanks for this inspirational thread. This process has helped me better define what I’m trying to do, and I’m now finding myself spending spare moments hashing things out, where before I’d get lost menu diving and mapping controllers unless I had hours to spare.
This is a very slippery slope tho… On top of everything else, the Zynthian is definitely a gateway drug!
@Jacco, how are you going with your routing and setup? Have you got it working reliably inside the Zynthian?
P.S - The samples in the track I shared were recorded by a fried whilst he was in Ireland in 2016. He used a shortwave radio and apparently needed a rather large antenna to pick up this station. The (conspiracy?) theory is that foreign intelligence services still use encoded messages like this because the recipient can be almost anywhere in the world, and receive instructions without fear of being traced through a phone call or Internet connection. This was from 12227khz which some claim is Russian Intelligence, tho this sample sounds British.
They were sequenced and played on the Zynthian using a sound font made on my computer. The static in the track comes from the same source and was recorded onto and played back via a four track.
It’s worth drawing a schematic in KCAd to help ! 
Wow thank you @jofemodo that’s quite an honour! 
@wyleu I’m nerdy enough to have a map of my network drawn up in draw.io, I don’t know why I didn’t think of mapping out my audio routes!
@gr0k we are hopiong to implement a more mixer-like audio infrastructure within Zynthian. (See this thread.) This may be what you are looking for. The plan would be to allow typical mixing desk audio routing and features but of course there is only so much grunt in the box so you always need to be aware of how much you are asking of it. For example, I have configured one of my Zynthians with an audio chain for my guitar and a few synth / drum engines and it is on the edge of xruns. I need to tweak it so that it will reliably perform at rehearsal / performance.
Thanks @riban,
I did actually get almost everything I wanted working, but the issue was patching, retaining, and restoring the routing. It just isn’t/wasn’t? possible (with the Zynthian UI) to route inputs/outputs to parallel effects and utilities, and even after getting everything routed with Patchage, Zynthian struggled to keep the routing when adding/changing effects, reloading saved states, or rebooting.
As I said tho, it’s clear that I was asking too much of a poor Raspberry Pi. EQ, effects, mixer, compression, routing loops, instruments, samples. It’s actually amazing it held up as well as it did!
The Zynthian is such a powerful unit, and can do almost anything! But in the end I had to be realistic about its capacity. I love that as my setup evolves it continues to not only find a home, but find itself essential, picking up the slack from other devices that lack certain features.
The Zynthian’s flexibility is almost its own worst enemy. It’s a great sequencer, MIDI router, drum machine, synth, effects unit, mixer, etc etc etc, but because of that you think oh great I’ll just use the Zynthian and after loading it up with three or four different tasks you quickly end up with complex routings and controller mappings that usually work but, in my case at least, turn out to be not that much fun to use.
The Zynthian can be a creative powerhouse or a utilitarian workhorse, but not both at the same time. In my instance at least where I’m fortunate enough to have found some cheap and borrowed gear locally, delegating a couple of roles to dedicated devices freed the Zynthian up to do things my other devices couldn’t, and the Zynthian has turned from functional utility back to inspirational instrument.
I’ve been staggered by what the Pi can manage even back to the Pi2 days.
The basic design of the zynthian leads to this. It’s constructed as an audio engine configuration device that we have added layers, initially as a way of presenting audio in data to the infrastructure and then as a tool to allow manipulation of those channels and by extensions engines.
So we have a set of engines with routing wrapped round it.
Which is possibly the wrong way to view it. It’s really a cross bar router with a set of engines and modifiers wrapped round it. with devices being both a source and destination on that router.
Think back to the VCS3 and it’s patch board approach as a solution.
The patch lead interface of MOD-UI certainly played it’s part and is a excellent way with a few nodes but quickly gets messy as it allows more and more manipulation.
We have good list manipulation and an interface ( the sequencer) that addresses xy manipulation. A press on a crossbar button takes you through to parameter screen. 
It’s the basis of what’s going on but of course as you dig down to more careful consideration you move back into the tinbox on the floor model.
and then of course there is Nord Modular routing.
Which allows infinite modulation . . .
And then you get it to the stage and you want . . .
@gr0k looks and sounds great!
My setup now consists of an Akai MPC1000, Fostex DCM100 (midi controlled 1U analog rack mixer), Dave Smith Tetra, and a Lexicon LXP-1 (and later also LXP-5) multi fx unit, all built into one rack unit. A lot more heavy than the Zynthian, but pretty reliable so far. I decided to leave the Zynthian out of my setup for now and stick to some old school midi compatibility. I’ve found using the Zynthian as a sampler gave too much latency combined with the Behringer UMC1820 for additional outputs, even with reduced buffer size and many xruns. I switched to the MPC as a multi timbral sampler, and noticed a big difference here. And I do need the extra outputs, as the internal mixer functions of the Zynthian sadly did not work as I’d like, mainly because the internal routing setup using auxes, was not remebered correctly in the snapshots. I decided to use a Fostex DCM100 instead and store all the settings via MIDI inside the MPC for each project I’m working on. I ended up using the Zynthian only as a multi fx unit connected to the auxilry outs and ins of the Fostex DCM which worked well. As I’m now storing the Synth and Mixer state inside the MPC via Sysex, I was researching if this was also possible for the FX, so I could actually recall an entire project including FX via MIDI, and decided to add the Lexicon LXP-1 and LXP-5 (which still has to arrive), and this possibility doesn’t exist for the Zynthian. Also the Zynthian MIDI recorder gave me some problems, where note-off messages were not recorded, so I’m using the MPC for this purpose as well. Right now I’m still using the Zynthian as a stereo audio recorder and possibly as a complex MIDI processor via Pure Data (which I still have to get working). Other than this I sadly I don’t have a place for the Zynthian yet!
Interesting! I have a DCM100 shooting idle as well as the mixtab control surface. DCM109 is quite noisy and has limited routing and eq. It is only 7-bit (MIDI) resolution so zips on adjustment. I can see it can act as a simple mixer to recall preset states. I am kind of encouraged at that level of acceptance as I think Zynthian could perform better.
Yes it’s true that the 7-bit resolution is problematic, mainly for volume. Right now I’m controlling the instruments’ volume directly via CC7, which solves the zipper noise. For fx sends and panning I didn’t notice any problems here. EQ is a bit limited but I can shape the sound quite a bit inside the MPC, and the Tetra, before I make the last adjustments on the DCM. Routing is very peculiar in the sense that you can only choose aux 1 or aux 2 per track, instead of using them simultaneously. This is something I have never seen on any mixer, but it’s a “funny” limitation I can work with. My first choice was actually a Yamaha Pro Mix 01, which worked great and I loved the sound of the FX, but it was just a bit too heavy for live use, especially because it has more channels than I need, and motorized faders and such. Ah and I forgot to mention that I’m controlling everything from a Faderfox EC4 unit, which works amazing!