Sync HD issues with PT 8

[SteveH44]

After configuring 2 new I7 Intel computers running PT 8cs2 on Leopard 10.5.7, there would appear to be a bug in either the Sync HD firmware (v221) or in PT8 itself. Here's what happens - We use the external word clock out (1x256) of the the Sync HD to clock other outboard pieces of equipment (ie. time code Dat, DA-88's, external A/D converters), and had noticed that when ever a session is loaded, the external equipment would fall out of lock for approx. 1 sec., enough to cause certain equipment's to need resetting.
We put a scope on the output of the word clock, and found when the Mac is turned off, the Sync HD would output 35.7 Khz. word clock. When the session starts, the Sync HD snaps to 48 Khz., stays at 48 Khz until the computer is powered down, when it drops back to 35.7 Khz. Why is this a problem, we use this external equipment, often without ProTools running, which would cause the audio to be pulled down (which is usually outside the tolerance of some digital gear), when the computer is off - not good. Under the same computer running version 7.42 and Sync HD firmware 2.11, this is not a problem. The Sync HD continues to put out 48K word clock even when the machine is turned off - this is good!
Talked with Tech Support over two days, but this does not appear on their bug list yet, and there doesn't seem to be a work around for the moment, so it's back to v7.42 for now.
Any thoughts?

TIA

[hummerZ]

I'm running a Sync I/O locked to blackburst on PT7, and it behaves similarly. It loses sync momentarily when starting PT, when opening a session, and when importing a quicktime file. Lets out a nasty pop at these times, too. Never figured it out.

[Chief Technician]

Originally Posted by SteveH44

We put a scope on the output of the word clock, and found when the Mac is turned off, the Sync HD would output 35.7 Khz. word clock. When the session starts, the Sync HD snaps to 48 Khz., stays at 48 Khz until the computer is powered down, when it drops back to 35.7 Khz.

What is the SYNC HD's clock source when you do not have Pro Tools active? I have always found that with the SYNC I/O, when Pro Tools is not active, that it reverts to Loop Sync mode, instead of locking to Video Ref, which is what I have it set to when Pro Tools is active.

I ask because if the SYNC|HD is reverting to loop sync, I wonder what would happen if you changed the clock source setting to video ref? Does it still output 35.7kHz?

I haven't paid close attention to this, but I haven't observed this problem with a SYNC I/O and v8...yet.

[Postman]

I'd look at how SyncHD is set when it is offline. Use the front panel buttons and indicators.

I do not have SyncHD, only SyncIOs with every version of Pro Tools. They have never changed sample rate when Pro Tools quits. System6000 will tell me if the sample rate changed and to what, and the monitor controller mutes at any "in between" rate like 37.5khz. There is no word clock interruption here when sessions close or PT quits. There is a word clock interruption when PT launches or sessions open, as PT takes control of the SyncIO and resets it to the desired sample rate. My System 6000 always throws up a red flag that has to be dismissed by hand. It has always been that way. I don't know why there must be an interruption when sample rate doesn't change, but there is.

[SteveH44]

We have tried throwing away all user PT preferences, with no effect. We have since retro-graded Pro-Tools to v7.42, and all problems have gone. From what I can tell, it has to do with the way Pro-Tools initializes the Sync HD and the 192 I/O, since the word clock glitches at the load-in and when the session quits. Unless you don't have equipment that is sensitive to losing work clock, or a scope to see the word clock cave-in for a second, you won't know. Looking at the tally lights on both the Sync HD and the 192, there seems to be a lot of switching between internal ref, loop, and which device is Loop Sync Master. Below is a sequence of boot-up, PT launch, and PT close.

Computer off - Sync HD = int/vso, Loop Master
192 I/O = loop, 48K
PT Launching - Sync HD = no change
(pre crash) 192 I/O = Loop Master, int, 48K
(post crash) - Sync HD = Ext Video SD Ref, 48K, LTC
192 I/O = 48K, loop, Not Loop Master
Session Close- Sync HD = loop, Not Loop Master, 48K
192 I/O = 48K, Loop Master, int

[DigiTechSupt]

We are currently investigating this issue and I hope to have some info shortly...

[SteveH44]

Just an update. Installed cs3 release this AM, but no change to this current problem. Word clock still corrupts during session load, and session close. We still have an open ticket on this problem with CS. It would be nice to know whether it will be resolved in coming "cs" releases, or whether it's not on the Digidesign radar.
Last response from customer service and DigiTechSupt, was its being investigated.

Steve
LA Studios

[Craig F]

Originally Posted by DigiTechSupt

We are currently investigating this issue and I hope to have some info shortly...

I'll say it again:
The Sync / Sync HD should stay locked to what ever house sync is (bi-level, tri-level, or word) in it's standby state.
Or whenever a session is not open.

[Eric Seaberg]

Ours switches to something else, as well. I usually have to set it manually on the front panel after powering down PT8. It stays there until another cycle with PT.

Glad Digi is looking into it.

BTW Craig F, this is ONLY with the Sync HD. All of our original Sync I/O are rock solid with PT off.

[smc917]

Anybody ever get to the bottom of this?

We are using a Sync IO and Machine Control. Pro Tools/Sync IO supplies time code and the console chases this code. The console provides transport control via Machine Control.

We are not sure why we lose sync momentarily when we open and close a session in Pro Tools. PT 8.

Thanks,

Dean