Random -6101 errors

[RobAnderson]

Today, while doing another test run of 1 hour 33 minute concert recording, Pro Tools spit out a -6101 error at 21:53.385 (and stopped rolling).

The session is 1 Stereo and 22 Mono Audio Tracks
No Plug-Ins; No Master Fader

Here are my Playback Engine settings:

Engine: Profire Lightbridge
Buffer size: 128 samples
Host Processors: 4; using 95%
"ignore errors..." is checked; "minimize add'l I/O latency" is checked
No Delay compensation; DAE Playback buffer: Level 2/Normal
"optimize for streaming..." is checked

Here are my DAW specs:
15" MacBook Pro
All networking, Bluetooth, and Energy Saver features are diabled
2.66 GHz i7 (dual core)
4 GB 1067 MHz DDR3 RAM
OSX v 10.6.6
PT9 v 9.0.1

I am recording to a LaCie d2 Quadra.
The daisy chain is:
MacBook->9" FW800 cable->LaCie->1m FW400 cable->Lightbridge

Though this is the first time I am really documenting a problem, when I first put this rig together I had a number of issues, some of which I think I solved, but this error has come up several times before - even with larger H/W buffer sizes.

Yet, for the past couple of days I have done nearly identical test runs using these settings (except I was using 2 mono tracks in place of the stereo track) with no problem whatsoever.

But really, with this much horsepower, this computer should have no issue with recording 24 tracks at 44.1/24-bit - even at smaller buffer sizes.

Most of my work is recording live events, so random hiccups really disturb me.

[HD2]

You computer has 4 processors and you are allocating them all to protools. That doesn't leave much for the rest of the system. Try dropping down to 3 and see if that helps.

[RobAnderson]

Thanks HD2. When I first started this rig a few weeks ago, I was using 3 processors.

But the reason I went to 4 processors in the first place was because I was getting lots of these sort of messages at first (can't recall if they were all -6101's, but I was being told to increase my H/W Buffer size). Increasing to four seemed to fix this problem.

Admittedly, that was with PT v9.0 and OSX 6.4. At the time, I was merely trying to play back a (brand new - i.e. session created in PT9 and audio was imported) 24-track session over the built-in output of the Mac (using the Aggregate I/O if I remember correctly) - not trying to record.

I'll give it another try, but given the random nature of this problem it will be hard to say whether or not it is actually "fixed".

[Holly73]

Do you need to monitor through PT? Otherwise you could also try a bigger buffer size.

[RobAnderson]

Hi Holly

For this particular interface I do need to monitor through PT.

Again, it's hard to say if changing the buffer really fixes the problem since it has not had trouble with this buffer size in previous runs. How many weeks will I need to run tests before I can be assured of its reliability?

For live tracking, I could run as big a buffer as I wish, but I also bought this rig with the hope of running sessions. Even 128 samples is large enough to provide noticeable latency in a headphone mix.

One reason I have used PT for so long is its stability, but it seems that this is no longer the case.

[RobAnderson]

Just because I could, without changing anything I re-ran the exact same session today and it recorded the whole thing without a hitch.