Digi 002 error inputs

[jimijo]

Hello everyone, I'll tell you if you can help me ...
I have a Digi 002 rack connected to a MacPro 2.1 with Mavericks and Logic X, the card to reproduce the tracks has no problem but when I connect for example a guitar, after a while (it can be about 3-4 minutes) the sound, only the on the guitar, it starts to sizzle and only stops when in the Avid 003 Family application where it says "Clock Source" I change the value to any other option but it sizzles again when another 3-4 minutes pass.
The truth is that it is something strange ....... I thought it could be the cable, I have already asked for one, when I get home I try it, but in the meantime, let's see if you can tell me what it could be, I hope it is not internal fault of the inputs.

Greetings and thanks.

[JFreak]

Take a look at the firewire light. If it is blinkin or otherwise not lit continuously, you may be suffering the infamous "power harness problem" which mostly first manifests itself as a clocking problem.

[jimijo]

Thanks for answering,
the lights both the front (1394) and the back (link) are on.

[JFreak]

Good then. But do yourself a favor and google a bit about this "002 power harness issue" and if you have it you can fix it yourself if you can use a screwdriver.

[jimijo]

I already cleaned the contacts but that does not seem to be the problem, it is when connecting something through the input that after a while the sound begins to sizzle, but only the sound of the input, if you have tracks they are reproduced perfectly, could it be the drivers? I use Mavericks, they told me that El Capitan is perfect, could that be it?

[JFreak]

El Crapitan is the worst version ever, avoid at all cost.

Does this happen on all inputs or only one input? That is the key for your troubleshooting. If it is only one input, maybe that input is just bad. If it is everywhere, maybe something wrong with the clocking. And in that case simplest remedy could be buying a new FW cable.

[jimijo]

It happens on all inputs,
so could it be the wire?

[jimijo]

I just realized that if I leave everything without changing anything, the sound is fixed but it is heard with a lot of latency

[JFreak]

Latency would be likely caused by your playback settings. For mixing larger buffer is nice, but I am sure you cannot record with higher settings than 256 buffer.

[jimijo]

No, I mean that when I connect a guitar, for example, it sounds good, without latency, then a few minutes pass and the sizzle starts and if I leave it longer the sizzle is removed but it is heard with latency.
That is the sequence of the error.