Audio Dropouts with InstrumentsRack Midi Clip Launch...

[hgt]

Yo,
i have been using the 64bit beta for 2 weeks now and got the problem that my audio drops out for a moment when i launch a midi clip on an instrument rack track.
cpu spikes shortly from 21 to around 70 and then slowly goes back down to 21 when the midi clip is triggered and audio stutters for a moment.

i have 8 different vst's in the instrument track:
ni razor
ni skanner xt
faw circle(jbridged)
refx vanguard(jbridged)
refx quadrasid(jbridged)
tone2 gladiator
ff twin2
sugarbytes cyclop

i change between them via clip-envelope-chain select plus program change.
when i use any of those plugs in a single track, patch/program change at cliplaunch works fine(even with the jbridged ones) no audio dropouts there.
my set consists of 4 audio tracks with recorded loops and 4 midi tracks(2x synth instrument rack + 2x fxpansion geist).

is this a bug in the beta or is there a workaround???


my specs:
macbook pro quadcore, 8gb ram, ssd drive, os 10.6.8, ableton8 64bit(latest, 512samples buffer), korg zero8(audio+midi), apogee duet2(audio), faderfox lv3(midi), timefrog3(midi), ipad cntrl apps(konkreet performer, lemur)

[Tysonviolin]

I'm having similar issues with audio and midi clips
Live 8.4.6
15" MBP Summer 2012
OSX 10.8.1
16gb RAM

plugs:
live suite
predator
blade
sub boom bass
punch
ik classic multiband
bigstep
izotope stutter edit

[[mal]]

Hi,

My first question would be if this is new for the 8.4 beta.
Please compare the 8.4b6 (32 bit) and the 8.3 release version. If you see noticeable differnce in CPU load and frequency of glitches it is a new and very serious problem we would address.
- when comparing, please do not use Jbridge, but the 'normal' 32 bit version of the plugins to eliminate as many external factors that might give you additional system load.

Best,
Mads

[hgt]

ok,
i did a deeper comparison of the issue with 8.3.3 and 8.4.b6.
it is definitely better in 8.3.3(no jbridged plugs) but also there.
in some cases i get dropouts when changing patch only in currently active synthplug and in other cases audio goes on smoothly even when plug+bank+patch is changed.
i could not determine certain plugins that work better or worse in the 'ableton instrument rack'. it seems to vary on the patch or mood of host.
e.g. i get a dropout when changing a patch in ni razor but got no audio problem when changing bank+patch from vanguard to gladiator...
is it that 'ableton instrument racks' just don't work well with 3'rd party plugs maybe? or was the concept of 'instrument racks' never really stable? i did not use 8 instruments in a rack before thus just noticed it on the beta ...
best solution will be to avoid 'ableton instruments rack' and work with a bunch of midi tracks, uargh.

[hgt]

allright,
i restructured and am using simple 'grouped tracks' instead of 'instrument racks' now.
resolved! no more audiodropouts with the same plugs this way!
new problem now is that my clip launch controller(faderfox lv3) doesn't like the 'grouped tracks' channel and ignores it.
looks like i got to find out how to twist that midi remote script.
where can i find information regarding 'grouped tracks' - clip launch scripting???

thanx+cheers,

[[mal]]

Hi hgt,

Thanks for the information, its very helpful for tracking this onwards.
As you point out there is a CPU behaviour difference when using instrument racks (will run on one core), and when grouping several tracks (will run on several cores) which is by architecture.
The dip in performance from 8.3.3 to 8.4 is however concerning.

Please contact support on the matter at support@ableton.com and attach the project you made with 8.3.3 and a status report, then we will reproduce this internally.

Best,
Mads

[[mal]]

Hi,

There is a larger thread on performance issues. Please follow and post your input on the problem there:
viewtopic.php?f=46&t=184822

I will lock this thread to avoid several threads on same topic.

best,
Mads