Sync issues with multiple 96 i/o system

[[email protected]]

Greetings,

I am stumped! I have a Protools HD3 system running on an old G5 with 3 96 i/o interfaces. PT 8.01 with 10.5.8. I have used this system reliably for many years with no major problems in my studio commercially.

This past weekend, I disassembled the system and took it out to record a large on location job, using some other borrowed digi interfaces to track 48 tracks wide at 48k 24 bit. All went well.

I reinstalled the above 3 96 i/o rig back in the studio after the on location job, and am now having a problem with getting the 3 96 i/o interfaces to work (sync) properly. Here is the problem...

I have tried numerous configs (2 96i on the first card, 2 96i on the second card). What happens is the second and third interfaces experience a dig static pulse every 30-40 seconds...a loud single static pulse accross all tracks record enabled that are feed from any of the 2nd or 3rd i/o inputs in analog mode. The interface hooked up to the core card to the primary port is not experiencing this issue. I have been around long enough to realize that this is most likely a digital sync issue from the second and third i/o to the first, at least that is my thought.

I do have loop sync connected as recommended (loop sync out of i/o 1 to in of i/o 2, out of i/o 2 to in of i/o 3, out of i/o 3 back in to loop sync in of i/o 1.

I have the hardware setting on i/o 1 set to internal clock, as well as the other 2 interfaces (dig master clock set to 96i internal clock). What am I missing? I am loosing my mind...

I have replaced the main digi cable to the core card / first i/o...same issue. I ended up hooking up just one 96i last night to get through the tracking session (tracking only 14 analog inputs). But...I HAVE to get this rig working today. HELP!

Thanks,
Alan / Starfields Productions

[JFreak]

It seems to me that one of the word clock cables is broken. Luckily those are dirt cheap and you can do them yourself as well. Here's now you troubleshoot:

1) Only connect one interface to core card, one at a time, and verify that all three boxes work well (no pulses). This will just verify that boxes internal clock is okay and you have a working digilink cable. Basically you would also want to test all your digilink cables with one box as well, just to be sure that they are working perfectly.

2) Connect two interfaces to core card, obviously only using two word clock cables. If it pulses, change one cable. If pulsing stops, you have found the broken one. If it didn't, change the cable back to original and switch the other one. If the pulsing stops, you have found the broken one.

3) If you cannot get pulsing to stop on step two, switch one interface and repeat step 2. If the pulsing stops, you have found one interface with broken loop i/o. If it didn't, switch the box back to original and switch the other box and repeat step 2. If the pulsing stops, you have found one interface with broken loop i/o.

4) If no combination stops pulsing, switch the daisy-chaining digilink cable to another one (can be a long cable as well) and repeat steps 2-3 until you find a combination of two boxes and two clock cables that work well (no pulses).

This way you can find out which clock cable(s) or digilink cables have broken on the road, or if there is a problem in loop sync i/o of one of the boxes.

As always, whenever you have trouble like this, start simple and build one block at a time, to see when things start to go wrong.