[ardour-users] Weird lockup thing

[Nathaniel Virgo]

I'm not sure whether to post this to mantis as I'm not sure if it's an 
ardour or a plugin issue or just something odd about my system, but 
every now and then when I'm playing with LADSPA plugins my system 
suddenly becomes really sluggish, with the screen updating about once a 
second.  So far it's only happened when using the TAP Reverberator or 
the GLAME Highpass filter (and possibly with the Tube Amp with tone 
controls, I can't remember).  It's also so far only happened when using 
Ardour, although I haven't played much with plugins in other programs on 
this machine yet.

Ardour doesn't get kicked out by JACK and the DSP usage meter doesn't go 
up (it stayed at 11.2% last time it happened).  The response time gets 
slower and slower as time goes on but if I manage to kill ardour or 
disable the plugin before it gets too bad to do that it goes straight 
back to normal.  If it gets too bad I have to reset the machine.  
Sometimes I can hear a click at longer and longer intervals, which I'm 
guessing is a buffer's worth of audio arriving at the soundcard.  It 
seems to happen at a fairly random point when I've been using the plugin 
for a while, but last time it happened it was just as the GLAME filter 
stopped recieving any input, which makes me think it could be a denormal 
thing maybe?

I'm using QJackCtl - my .jackdrc says /usr/bin/jackstart -R -t5000 
-dalsa -dhw:0 -r44100 -p512 -n2.  This is a pretty standard Planet CCRMA 
install and the problem happens in CCRMA's ardour beta11.2 and beta16.1 
which I installed from the tarball.

It's a second-hand laptop so I'm not entirely sure about all the 
hardware but the CPU is a P4 2.6 GHz, the soundcard is the onboard one 
for the time being (driver seems to be snd-intel8x0 maybe?) and I think 
most of the other stuff is made by SiS.

Any help you can give me or advice about where to report the problem to 
would be much appreciated.  I can provide more information if you tell 
me how to get it!

Nathaniel.