Weird issue I'm having.  Please note:  I was not having this issue once originally set-up, this issue started happening about a day after I got everything working.  For some reason, any time that I try to play a something that should be coming through Kontakt 5, it only plays back the beginning of each note, sometimes.  It is very choppy and almost blippy sounding.  Please help!

Also, on a Mac, should I be using Kontakt AU in my playback configs, or Kontakt VST.

Thanks!

If you're on a Mac, I would recommend using Kontakt 5 as an AU.

Have you checked your ";Audio Engine Options"; in Sibelius? In particular, the interface, buffer size, and sample rate settings may have an impact on performance and what you actually hear. If you're unfamiliar with what these things are, you should be able to learn more from the Sibelius Reference.

I am having the same issue. The samples are cutting off shortly after being triggered. For instance, during playback the vibes are sustaining a whole note, but the sound cuts off about a beat and a half after the whole note is played. Also, a suspended cymbal roll will cut off before its peak. I am using the Audio Units version rather than the VST. I have looked into and played with the sample rate and buffer size, but noting has worked. If I create a new playback configuration, it works fine for maybe 15 minutes or so.
Also, occasionally Sibelius will crash when I try to save files which include VDL sounds. (That's an Avid issue I guess, but I didn't know if you knew anything about that.)
I am having numerous issues with VDL and Sibelius 7. I think it is mostly Sibelius issues and not your issue.

Geoff Martin
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Mac OS X 10.7.3
3.4 GHz
8GB RAM
VDL 2.5.2
Sibelius 7.1.0

[quote author=GeoffreyDMartin link=topic=4239.msg22229#msg22229 date=1329943048]
I am having the same issue. The samples are cutting off shortly after being triggered. For instance, during playback the vibes are sustaining a whole note, but the sound cuts off about a beat and a half after the whole note is played. Also, a suspended cymbal roll will cut off before its peak. I am using the Audio Units version rather than the VST. I have looked into and played with the sample rate and buffer size, but noting has worked. If I create a new playback configuration, it works fine for maybe 15 minutes or so.
Also, occasionally Sibelius will crash when I try to save files which include VDL sounds. (That's an Avid issue I guess, but I didn't know if you knew anything about that.)
I am having numerous issues with VDL and Sibelius 7. I think it is mostly Sibelius issues and not your issue.

Geoff Martin
===
Mac OS X 10.7.3
3.4 GHz
8GB RAM
VDL 2.5.2
Sibelius 7.1.0
[/quote]

Geoff - are you using Kontakt 4 or 5? How many instances of Kontakt do you have activated? When possible, it's a good idea to keep the activated instances to the minimum necessary. What you're describing sounds like a memory or polyphony issue. Are your VDL samples streaming from an external drive?

What is the difference between VST and AU?  What is the advantage of using AU?

AU (Audio Unit) is specific to Macs. VST works on either Macs or PCs. Essentially they're just two different plugin platforms that do the same thing. I'm not sure you'll find an advantage of using AU vs. VST on a Mac. Since AU is somewhat default on a Mac, I usually steer that way.