What do you mean assign as many as I can to the same MIDI port? You mean in the mixer? Or in the Manual Soundset setup (Playback Devices dialogue)? Wouldn't that preclude the ability to have more than 16 channels? Do you mean I should test to see if it's a particular MIDI port that is causing the problem? 

I have 48 GB of RAM on my slave, 24 on my master. Everything is SSDs.

VSL tech is the best!

mohurwitzmusic,

You could certainly try eliminating one particular MIDI Port or Ports to see if there's a fault there - though I'd be surprised if that were the source of the problem.

No, what I meant was allocate all 16 Channels on Port 1 before allocating the 17th instrument (and Channel) to MIDI Port 2, Channel 1 etc. From your earlier post (maybe I misunderstood?) it seemed as though you were distributing instrument (Channels) across Ports more widely.

I'd avoid the Mixer if you can. Sibelius works best when its Channel allocation is left at 'Auto'.

Have you tried starting from scratch (keep a copy!) with a poece that's behaves in the way you describe; and alloacting instruments to Channels, Yes, in the PlayBack Devices dialogue one at a time? And see when - if - there is a slowdown?

With that much RAM, it shouldn't be a hardware malfunction, I wouldn't have thought. Though, one last question - if on a PC have you tried restarting… there's no memory leak or runaway/zombie process, is there?

On Win 7. No definitely no zombie process. Restarted. Cubase works like a boss, it's just Sibelius. And it's only when I use my manual soundsets, because the Sibelius Sounds are fine. 

My channels are distributed sequentially, with no gaps in between. I suppose I could try to build it up again one by one, however I even ported my playback setup back to Sibelius 6 and the problem persists. Unless there is some kind of problem with this playback config being corrupted.

I may have to try reinstalling Sibelius. I did disable some file...some Plogue fil...because it was crashing Cubase when the two were open at the same time. Sibelius just never got along well with my audio drivers (MOTU 2408 Mk3 PCIe).

Although it's painful, classic troubleshooting steps begin with elimination, don't they?

That's where I'd start. Re-installing Sib. isn't too onerous. Yes, I'd do a full install - even with the .dll that's a nuisance

Then I'd intoduce manual soundsets one at a time and see if:

• either, one particular instrument/Channel causes it
• or, the latency grows one channel at a time - incrememntally

You're sure there are no duplicated Channels; and this is all using only VSL VI's - so not a Preferred Sounds issue?

Good luck!

Well, I am using my custom VIPro presets, not the ones that VSL created. 

No duplicate channels. All my channels are numbered and named from Piccolo to Doublebass.

Reinstall isn't too bad. 

Ugh! Thanks, though. I'll post again after I try reinstalling.

Now that I think of it though, I don't think reinstalling will do anything since it happens to a fresh install of Sib 6.

I still think that your best bet at this stage is to see whether you get the phenomenon as you introduce channels one at a time. If you do, is it incremental (which supposes one cause); or any one instrument/channel (which supposes another).

I'd also try different presets. Experiment with a variety of variables (after backing up) and see if you can isolate it that way.

Good luck!

That's very unfortunate and painful in Sib7. I also run a huge playback setup and the only chance to edit fluidly is to disable the instant playback of the note you enter or select. I forgot where to disable that, look in the playback preferences.

@mohurwitzmusic said:

But what's also strange is that if I do a lot of editing on one staff Sibelius seems to "wake up" and things are fluid again. But performing certain tasks seems to put the plugin "to sleep" again. Anything where I have to actually hear a sound can cause a slowdown (ie. clicking on a notehead, press R to overwrite a notehead), but if I just grab measures and copy/paste whole sections it's fine. I tried disabling "Play Sound as you Edit" and this doesn't help when playing back the full score is involved.

Ah, so you are having the same issue. Are you using manual soundsets that you created? Do you think it's just poor audio plugin handling of Sibelius? What about playback...does it take a while to initiate? Have you tried talking with Avid about this?

Yes, I run a huge setup with lots of custom modified manual soundsets. The guys at Sibelius (back then when they were still in charge) weren't able to replicate my problems due to the sheer size of my setup. It's not poor audio handling. It seems that Sibelius first crawls through the complete soundsets and plans the playback, those are my naive words. I used to be a beta tester. Don't expect any change in this behaviour anytime soon, you basically have to live with it. So follow my advice and disable playback upon note select, then there is solely the lag before playback.

Interesting. The funny thing is my soundset is SUPER simple. All my keyswitches are almost exactly the same for all my instruments, so I only really have 3 switch maps (one for low keyswitches, one for high, and one for percussion). And there's no way I have more instruments than the Sibelius Default Sounds. Yes, I have 130 or so tracks, but Sibelius has profiles for what must be 200+ instruments. So it must be the number of channels assigned in the Manual Sound Set, then? I guess I'd have to manually assign the channels then for each new composition. That sucks. What really sucks about it was how nice it was to do Instrument Changes that automatically assigned to new channels.