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Hello.

I've been working on a project where I am noticing random digital clicks. This had never happened before.

At first I thought it was a problem with my slave computers, since I noticed this when composing using VE Pro. A lot of it was a Celesta part, so I figured it was the natural noise of the instrument, but not really.... I would immediately play back where I heard the click, and the second time it was gone... no click. Hmmm...

Then it happened when mixing audio. One click here, one click there. I thought the audio had been recorded with the click, but upon another play, no click there anymore (but I'd hear another one somewhere else). I soloed the track, and this kept happening. Not too often, but enough to ruin the project.
When I solo some instruments, it sounds a little jittery. Like some kind of distortion. Subtle, noticeable only when soloing some instruments.

I thought this was a DP thing. I reinstalled. I repaired permissions (don't know what for), checked the disk, etc. But then, I also heard a few random clicks when playing the file from the Finder! First I hear it, then I don't.

What's going on?

This might be a clocking issue between my Track 16 and my Tascam DM-24, which are connected via ADAT. It's mostly for monitoring. The only time DP records from the Tascam is when I record a singer, which sounds fine to me (no clicks).

I know everything is supposed to reference the same clock. So DP is set to internal clock, as is the Track 16's. Both read internal. My Tascam also reads internal. I thought it should've been set to "Word 44.1", but it won't let me, so I left it like that.
I'd rather not mess with the Tascam clock unless you tell me to, since it's screen is practically unreadable by now. Besides, I had never noticed this before, so either, a fairy changed the setting, or I've had it wrong all along since I got my Track 16.

Any help or troubleshooting would be appreciated. Thanks!

The obvious thing was to try changing the clock reference of the Tascam, but it will NOT let me do it. The other option I see there is to set it to "Word", but it then throws a message reading "No Signal".

I remember now I tired that when I first set it up a few months ago, and I got the same, so I just left it.

It wouldn't make sense to set DP to sync to ADAT, so I don't know what else to try...

Ok, I can't work like this. It definitely didn't happen before. It's so strange!

The Tascam will not let me change its clock to anything except "Internal". But it's supposed to be synced, via ADAT, to the Track 16, which I have set to INTERNAL (it mimics DP, which is set to Internal too, since it should use the internal clock of the interface (computer?), correct?

I double-checked I'm using the same sample rate everywhere (44.1)

The only thing I could change was precisely that setting in the Track 16 only (and leave DP as is, in Internal). I set it now to ADAT, and see what happens as I continue working.

I will report back, but any suggestions would be very appreciated, since I need to start printing, and I have no idea where those clicks are coming from (they sound like a bad soundbite edit without a crossfade... trkt... or something like that).

Well, I'd do a few things, some of which I'm sure you've already done.

Restart

Disconnect and reconnect everything (powered down, of course)

Repair permissions

Update drivers

Reset PRAM

Check peripherals and the computer batteries

Try the system without the T16 and/or the the Tascam attached.

Reapply the drivers

Delete all plists (including the MOTU AUDIO one(s)

Check your cables!!!!!! Cables can and do go bad and (as you know) in the digital realm that can be disastrous

Check for any power supplies that might be emitting sound via an adjacent cable.

Anecdotally, I added a 30" Apple Cinema display last night to my two 24" displays. When I turned the trash can back on, the Cinema display was dead. I rechecked all the connections (or so I thought) and it was still DOA. I failed to check the USB connection, which the Cinema display needs for brightness. Duh! It was working before I added the other two monitors back in, but not afterwards. Again, it was a USB cable. Not what's going on with you, but a lesson to be sure. It can always be as simple as a single cable or dirt on a contact.

I've never been able to get a perfect sync using ADAT, either between a Tascam unit, a Mac and MOTU equipment or between two MOTU units. I've had this happen on Macs as far back as a PM8600. Looking at specific channels on a recording, I can sometime see periodic glitches, so it appears to happen on both record and playback. On a low frequency waveform that has been moved or copied via ADAT when ADAT is used for sync, I can find spots where it appears to periodically resync. Looking at various meters, I can often see one bit of noise on channels where there should be nothing, usually on ADAT channels 7 and 8.

I haven't invested a lot of time in a solution because by simply changing the sync to word clock, these problems have immediately disappeared.

MIDI Life Crisis wrote:Well, I'd do a few things, some of which I'm sure you've already done.

Thanks, Mike.
Yes, I only did the most basic of those, but I will have to dedicate some time to do your suggested steps. I mean, I'll do whatever it takes.
If it's just the monitoring, then I'm not too concerned, as long as DP operates internally correctly.

bayswater wrote:I've never been able to get a perfect sync using ADAT, either between a Tascam unit, a Mac and MOTU equipment or between two MOTU units. I've had this happen on Macs as far back as a PM8600. Looking at specific channels on a recording, I can sometime see periodic glitches, so it appears to happen on both record and playback. On a low frequency waveform that has been moved or copied via ADAT when ADAT is used for sync, I can find spots where it appears to periodically resync. Looking at various meters, I can often see one bit of noise on channels where there should be nothing, usually on ADAT channels 7 and 8.

I haven't invested a lot of time in a solution because by simply changing the sync to word clock, these problems have immediately disappeared.

I'm relieved to read that, Bays.
I didn't know ADAT sync could cause this. I never saw this with my PCI card. It was rock solid sync through TDIF.
Then perhaps I should not worry too much? I mean, the ONLY time I record through my Tascam mixer or Track 16, is when I'm tracking vocals.
I assume that's when it can affect me, but 99% of the time I record tracks digitally from within DP via its interna busses, or from the slaves via ethernet. Or, I bounce to disk. I mostly use the Tascam to monitor.

So as long as I do this those clicks should NOT appear in the recorded tracks, correct? Or is there an instance where this could affect DP when recording internally?

So it it's only a monitoring issue, I can go home peacefully and deal with it coming back from the break. But if it's affecting my recorded tracks, I will not enjoy myself until I solve it totally.

FMiguelez wrote: I assume that's when it can affect me, but 99% of the time I record tracks digitally from within DP via its interna busses, or from the slaves via ethernet. Or, I bounce to disk. I mostly use the Tascam to monitor.

So as long as I do this those clicks should NOT appear in the recorded tracks, correct? Or is there an instance where this could affect DP when recording internally?

So it it's only a monitoring issue, I can go home peacefully and deal with it coming back from the break. But if it's affecting my recorded tracks, I will not enjoy myself until I solve it totally.

As I said, I didn't spend a lot of time looking at the problem. I noticed it when linking a 828 to a 2408 using ADAT, and when moving a track from a Tascam device to DP when ADAT was being used to sync. I suspect if you have two devices synced with ADAT and record on from an ADAT channel you could get a glitch, because I see noise on some ADAT channels in that arrangement.