Digital Cracks/Pops AES 192 Digital IO - S/PDIF

[NateAlexander]

Hey all, got a troubleshooting issue that is driving me up a wall

our studio has a CDJ system hooked up through S/PDIF -> AES (Ch. 1+2) to a 192 on our HDX system, and lately it has begun to crackle and pop even when idle. another tech said he saw the Big Ben that's locking the whole rig go loco for a minute a while back while client was practicing on CDJ system.

my first thought was something happened with the clock, but every channel is fine, and the CDJ doesn't take sync anyway.

then i took a look at the SRC-- but it seems fine, the 192 is locked to the Big Ben, and the other component running through a digital to AES converter (but TOSLINK) isn't replicating this issue.

this sound to me always means something with clocking or sample rates-- any other ideas?

wondering if it's the Hosa, or just the cable, but that seems too easy...

ftr:

Mac Pro
3.3 Xeon
80 GB DDR3

2x HDX cards

2x Big Ben locking up:

1x 192
1x HD I/O

[Darryl Ramm]

The way I'd tackle this is simplify a much as possible and test until you find a culprit. If you suspect the CDJ DJ thingy (never used one) bung that directly into a HD IO or 192 IO with nothing else involved and play with it, or just leave it sitting there recording stuff.

And I'll point out folks on the Interwebs complaining about pops and crackles with CDJ products. e.g. https://forums.pioneerdj.com/hc/en-u...-320kbps-files

[JFreak]

Originally Posted by NateAlexander

CDJ system hooked up through S/PDIF -> AES (Ch. 1+2) to a 192 on our HDX system

How exactly? You mentioned SRC so I assume it is wired to the digital card (because the chassis connectors won't do SRC). Also while the audio data is same in S/PDIF and AES/EBU, there are other differences in the digital stream.

[s.d. finley]

Big Ben is the master clock for all devices except the CDJ player? CDJ goes into 192 via spdif and that 192 is clocked and locked to the Big Ben? Sounds like clock needs to be resolved between the CDJ and 192. 192's SPDIF inputs want to clock from the digital input which is the CDJ. 192 is receiving 2 different clocks. Hence the pops and clicks. I wouldn't clock the Big Ben to the CDJ and the CDJ will not clock to external devices so you probably need to go analog with the CDJ.

[NateAlexander]

In case anyone has a similar issue: I ran it straight to the S/PDIF enclosure connection instead.

Greatly reduced issue, although ultimately we have replaced the cable as well.