Unable to get Fast Track Pro SPDIF Out into Mbox Pro 3 SPDIF In

[JuanSalvo]

Hi, how's that going?
I'm currently having some issues connecting my interfaces over SPDIF, my idea is to use the Fast Track Pro inputs as the 7/8 INs from the Mbox Pro 3 (which are SPDIF).
The thing is that i can't get the Fast Track Pro inputs over the SPDIF out, is there an specific config or something i need to do to get them working?
i checked the manual and it mentions an stand alone mode which should allow me to do it

[Darryl Ramm]

Welcome to DUC.

There is not much for you to set up here so it's likely to be something simple you are doing wrong.

You actually have the Fast Track Pro physically disconnected from the USB cable and powered by a separate power supply so it's actually in stand alone mode? I expect any connection to a USB host might take it out of stand alone mode even if it's not being used by software on the host.

You have the Fast Track Pro S/PDIF out connected to the Mbox 3 S/PDIF In port? Check carefully you don't have the cable connected wrong.

You ideally should be using a 75ohm coaxial digital (or "video") cable not an RCA audio cable?

You've tried other cables in case this one is bad?

The Mbox 3 Pro you are using as the interface is set to clock from its S/PDIF in? You have to have this setup clock this way, as you have no way of telling the Fast Track Pro to clock from its S/PDIF input.

The session is set to 44.1Khz? Since that's the only sample rate the Fast Track Pro outputs, and the Mbox 3 Pro does not do sample rate conversion on it's S/PDIF input so you have to work at that sample rate.

How exactly are you determining there is no signal?

You have a track with the input(s) set to the S/PDIF input? Try defaulting the Setup>IO pages.

Does the Mbox 3 Pro monitor/control panel show S/PDIF inputs activity?

Failing that try getting the Mbox 3 Pro working with some other device with S/PDIF output, like a CD or digital audio player. If you have a headphone amp with S/PDIF input get that working with the Fast Track Pro.

Fast Track Pro are so cheap and not good sounding that I'd encourage you to find other preamps to feed the Mbox 3 Pro S/PDIF or line inputs. Or look for an interface to replace the Mbox 3 Pro. There is a very wide range of great interfaces out there from many vendors, and no need to purchase an Avid product.

[JuanSalvo]

checked the stuff you mentioned and after connecting the interface with a separate power supply and "another" breakout cable i was able to get it working, thanks for the help!

when i bought the mbox pro 3 didn't came with the breakout cable for the spdif in so i'm using a DIY one i made, took me a few tries to build it correctly but now seems to work fine