It works fine on stock kernel, 12.04 included -- the issue was specific to "rt" kernels , and should be fixed by the just-released version 4.0.2

This may be unfair, perhaps I shouldn't expect it to work.
I just downloaded a copy of Ubuntu 12.04 Studio, which supposedly has all the interesting audio and video packages installed and set up;  Ardour, QJackctl, etc., it is built on a real time (they call it "low latency") kernel.
Only down side is that it is a 1.9Gig download.

Now the tricky part;
I tend to check things out initially on virtual machines, under VirtualBox.
Jack throws a fault initially, but when the trial version of PTQ4 is started it does receive midi messages from my keyboard and they sound.
I suspect that this is just because it is already running.
The latency is TERRIBLE and even I can get 4 or 5 notes ahead of the sound when playing scales :-D
The trail version wouldn't load the pre-sets that I had downloaded from FXP corner either, I got messages about not having the basic piano models for which they were created - I think it meant that I can't load V3 pre-sets for particular V3 instruments onto/into different V4 instruments.

So, Virtual Machines are probably OUT for any sort of live playing, though I may keep one for experimenting and playing midi files.
In any case it doesn't make much sense to strive for low latency in a real time virtual machine that is running in/under a non-real-time O/S (Windoze).
Comp Sci 101; You can run non-real-time processes under real time supervision, you can't expect to run real time processes under non-real-time supervision.
==========================================================
In a separately built UBUNTU Studio 12.04 the latency is perfectly acceptable (for MY speed and complexity of playing).

Enough of the trial version, I have been tracking my FedEx shipment of the close out deal on V3.
It was within 10 miles (16 Km) an hour ago; in the next 10 hours it will circle around the neighborhood and I will probably get it by 6 p.m.  I might get to bed before day break.

Next step; I only have a single foot pedal to my (now very old) KX88 and it is very much a SWITCH (on/off) damper pedal.
The GPP 3 pedal unit is out of production, so I am searching for a 3 pedal unit that transmits as continuous controllers. 
Hmmm, are  una corda and sostenuto  "continuous" or binary on/off on physical pianos ?
I have never had to think about this before.
I will probably have to get a USB unit and route something through something else's "MID THRU".

Then I can revert to pre-set bunny role and just PLAY.

I just hope the registration and download server at Modartt stays up tonight :-D

It works fine on stock kernel, 12.04 included -- the issue was specific to "rt" kernels , and should be fixed by the just-released version 4.0.2

GREAT !!!

Then I shall change my plan and use a real time kernel.

Thanks

Does this also apply to Ubuntu ?
I was HOPING to do a PTQ install on Ubuntu 12.04 next week.

I'm running Pianoteq 4 on Ubuntu 11.10 - I'm not using the realtime kernel, though - and it works just fine.  I plan on upgrading to 12.04 LTS at some point during this weekend, so we'll see how that goes.

EDIT:
I missed the point about rt kernel, sorry.

Sincerely,
sloppy reader

:END EDIT

I've experienced this before with Juce applications and the current versions of Juce, and resurrected a forum post over at Raw Material concerning this.

http://www.rawmaterialsoftware.com/view...p;start=15

Near the end there is a patch suggestion by falkTX. I have tried this on my own test applications and can confirm that it does fix this issue, I'd suggest you take a look. I'm sure a lot of hard core Linux users who do audio work use the realtime kernel and this may be a major issue.