Multiple MOTU Audio Expresses, only one works at a time

[redsonola]

I'd be very grateful if anyone could help me with this problem. I have 2 MOTU Audio Expresses, and only one is working at a time. It seems to be a problem with the synchronization/clocks. Whichever one I set to be the Master Clock (using Internal time), that one works, and then the other one flashes (indicating I believe that it is not receiving any sync/clock info) when I try to use it (ie, I open any audio application and the 2nd one will start flashing, and then not working). I can switch which has the master clock, and this changes which one will work very reliably.

This is on Windows Vista (sigh, I know) and using USB, since the machine does not have firewire inputs.

If anyone has any additional insight, that would be helpful. Thanks so much.

[MikeHuntingford]

I would invest in a good firewire add-on card for you computer (make sure it has Texas Instrument chipset) and connect one MOTU to computer and the other to the MOTU. Set the one connected to computer as the master.

I've not done this but have read that this is the way to do it, as I am sure USB does not support the chaining you desire.

Mike

[terrybritton]

I would invest in a good firewire add-on card for you computer (make sure it has Texas Instrument chipset) and connect one MOTU to computer and the other to the MOTU. Set the one connected to computer as the master.

I've not done this but have read that this is the way to do it, as I am sure USB does not support the chaining you desire.

Mike

What Mike said!

USB does not support two units at the same time. You can use the second unit as a line-mixer and feed the computer connected one via S/PDIF, OR do what I did and invest in a TI based Firewire card. You will need two inputs on that card, one for each Express. (The second input is really a bus on a single line in most cases.)

The marketing dept. at MOTU heralds the ability to daisy-chain devices ("Just add another device!") but they neglect to mention this only works via Firewire.

In fact, they explicitly state, at the bottom of http://www.motu.com/products/motuaudio/ ... tures.html "Add another Audio Express (or other MOTU audio interface) as your needs grow via a standard Firewire or USB 2.0 hub." Tech support has confirmed this is in error.

Terry