i have had an mbox for a while, on xp with Pro tools 6.4. worked fine plugging my guitar directly into it. I just got a v-amp pro, which i run through s/pdif to my TC Electronics G-Major processor. This also has s/pdif out, which i want to run to the mbox. the tc is configured properly to my knowledge, and i have tried to configure pro tools to accept the s/pdif input. the settings on there appear to be correct and match in documentation. But all i hear when i connect my headphones is an annoying buzz. pro tools does not show any input signal. the mbox "spdif" LED lights up as soon as i switch pro-tools to use the spdif input, EVEN when no s/pdif input is connected. i thought that LED is only supposed to light when it has synched with the clock? regarding clock, i am setting it to use the clock on the input signal, not internal. also, i know the s/pdif out on the v-amp works properly, since it goes to the g-major fine and i am monitoring the analog output of the g-major. So, i plug the s/pdif out from the v-amp to the mbox with the same results. this leads me to believe that it is an mbox/pro tools problem. any help would be great. block diagram [guitar, analog] -> [v-amp pro, s/pdif 44.1kHz/24bit] -> [tc electronics g-major, s/pdif 44kHz, 24bit] -> MBox.

You have to set the clock from internal to SP/Dif. But I doubt, if I would trust an external clock by Behringer .

man, behringer has a bad rap. on a serious note, it is working fine. the tc electronics device sees it perfectly. like i said, that is not the problem. also, i have already tried your suggestion, which is right. from my original msg: regarding clock, i am setting it to use the clock on the input signal, not internal. basically, that means sync up to the external device. duh! i wonder if my mbox is defective.

nilz , Does your PT session sample rate match the incoming digital sample rate ? ...44.1><44.1 or 48><48... good luck,

have you tried the tc alone ?

or the behringer directly ?

is your g-major set for digital output?

just in case: did you record-enable the track & choose input only ?

I record-enabled, ya. everything is the same as when i have recorded before using analog ins. what is "input only" though?