Midi latency between live on a macbook and padkontrol

[nixt]

Hi everyone !

I have a problem which I have never been able to solve completely. I play live with a macbook core 2 duo 2.4GHz / 4Go RAM and a 7200 rpm internal drive. I use an Edirol FA101 firewire sound card and two usb controlers : a Novation Remote Zero SL and a Korg PadKontrol. I set the buffer size at 256, which works fine on my setup.
Sometimes, and only sometimes, I experience a latency that can be long enough to become a big issue when playing live. It happens mostly between the padkontrol and ableton. I use the padkontrol to play samples from ableton's sampler and to control effects. The latency is the same when turning a knob or playing a sample.
The strange stuff is that after a reboot, the latency disappears. But as I play, it gradually comes back, until it becomes impossible for me to play in rythm anymore. Sometimes after a few minutes of playing I experience a noticeable latency, sometimes it behaves well for a whole 2 hours long liveset.
I use Live 8.0.3 but I have had this problem with live 7 also.

Will anybody have any idea to help me ? At least maybe someone will know where that comes from...
(last precision, the energy savings setting are set to the best performance, the hard drive or the mac are not supposed to go to sleep).

Thanks a lot for your help !

[jlgrimes]

I'm having a similar issue with the kontrol 49 playing a little late sometimes. And rebooting the PC does help.

Reason or Sonar doesn't experience this problem though.

[nixt]

ok, now I'm getting a little irritated with this : I played in a club last night and after having plugged my macbook, the padkontrol, the novation remote zero sl and the edirol FA101 sound card, I decided to do a quick check in my headphones as the DJ before me was finishing his set. Bad luck, there is some latency between my padkontrol and live. I restart the computer, no change. I set the buffer size to 128 and then back to 256 and finally everything seems fine, no annoying latency. 15 minutes later I start playing my liveset and the latency is back, so much that I finally gave up lots of the "tricks" I intended to perform.
I want to say to those who will try to explain to me that the latency concerns my sound card and not the midi flow that I mostly use the padkontrol to control effects. And when I turn one of the knobs on the padkontrol, the corresponding knob in ableton should turn at the same moment because no audio is involved.
Maybe two usb powered controlers are too much for the macbook to take care of the midi signals properly and I should plug the padkontrol to a midi port instead ?
Please help me, I have some gigs planned and I wouldn't like this to happen again...
Thanks...

[Spr4wl]

This same problem is happening to me... in fact, it happened last night while playing a gig and really screwed me up. My set up is fairly similar... macbook, two midi controllers (APC 40, trigger finger) and an audio interface (presonus firebox). I've checked buffer sizes, computer CPU and memory loads, and everything else and there doesn't seem to be any explanation as to why it ONLY SOMETIMES happens. I know its not my external soundcard either because there is still an issue if I have audio running out the headphone jack on my computer... unless something is going on internally in my computer. I'm at a loss.

Nixt, I feel for you man... got a couple of gigs coming up myself and would like to be able to play some samples on my trigger finger.