Ardour 2.3/2.7 losing Jack after first playback, Ardour not fast enough.

I have a project that I was working on in 2.3 and I started getting this error.

JACK has either been shutdown or it disconnected Ardour because Ardour was not fast enough. Try to restart JACK, reconnect and save the session.
It got the point where I couldn't work on the project anymore.  I could open the project and playback my song, but as soon as I stopped playback that message would pop up and JACK would get Xruns. My session isn't extroidinary, it has 7 drum tracks that I recorded from Hydrogen, 2 guitar tracks and a bus.  It has 7 effects running which doesn't seem like a lot since I have run more effects in Abelton Live and Adobe Audition before.  
I investigated and tried to make sure my system was tweaked correctly.  I am running Ubuntu Studio Hardy with real time kernel 2.26.24.  I have my audio group setup in the limits file with unlimited memlock.  My system has a 1.8GHz Core Duo and 2GB of ram. I don't have any hefty daemons/processes running.  I am using a Edirol UA-4fx USB audio interface.  I have jack setup with 128 frames and 3 periods.  I got the same results when I turned the frames up to 1024.  Ardour plays/records fine in a new session with just a few tracks.  Other audio apps work fine with Jack.  I built .116 jack and 2.7 Ardour from source with optimize flags and still get the same result.  My hard drive is running in udma6 mode and gets 900MB/sec cached read and 40MB/sec buffered disk read.  I have run the realTimeConfigQuickScan.pl from http://wiki.linuxmusicians.com and all checks are good.  I am out of ideas and just want to make music, any help is greatly appreciated.

Thanks.

Okay, so after continuing my search for a solution I can across someone with a similar problem that ended up being cause by a bug in a effects plugin(freeverb). I had about 10 plugins in my project and I narrowed it down to the one causing the problem! TAP Equalizer. I don’t know what the actually problem is, but it causes ardour/jack to fall apart. Upon checking out the website for TAP it looks like development has been dead since 2004 so I don’t know if it will be fixed.

Ardour Rocks. Case closed.

Yep. I hit this as well recently. Freeverb was the culprit. Just getting back into recording, so still finding the best plugins. Stay away from Freeverb.

kddubb

try http://www.linuxdsp.co.uk for professional audio plugins for Linux. Stuff that actually works.

I can second the opinion of linux dsp -> since changing to his plugins (for most of my needs) - I never had any problems in my projects.

And they sound very good (to my ears).

"I had about 10 plugins in my project and I narrowed it down to the one causing the problem! TAP Equalizer. "

I think this is important information, so the case should not be closed until a note has been added in the plug-in list about this problem.

I have not used the equalizer, but the other TAP plugins i used has worked fine for me.

Regards,

Jens.

Ardour can’t be responsible for blacklisting any possibly badly written plugin, sorry. Some things Ardour and its developers have absolutely no control over and you are asking them to be responsible for literally thousands of plugins and their interaction with their hosts.

   Seablade